Found this article on London vs. Athens.

Τhe cumulative costs of the Athens 2004 Olympics have risen to $15 billion and is most definitely a prime reason for the Greek state’s dramatic financial crisis. Olympic spending left Greece with a hefty budget deficit in 2004, reaching 6.1% of Gross National Product, more than doubling the EU’s cap of 3%. Olympic spending also pushed up public borrowing in 2004 to 43 billion from an earlier target of 35 billion. Since then, Greek public debt has exploded exponentially. In 2010, it reached a stunning figure of $469.8 billion (142.8% of GDP).
The cost of the Athens 2004 Olympics security effort is truly astounding. Athens’ Olympic security bill alone was $1.5 billion, more than four times the security costs for the 2002 Winter Games in Salt Lake City and six times that spent for the 2000 Summer Games in Sydney. Athens Olympic security was originally based on a C4I surveillance project (standing for Command, Control, Communications & Integration) that proved to be a technological fiasco. The system is still unworkable, years after the end of the Games. Regardless of the system's dysfunction, I cannot over stress how absurd this project was for the Greek people. A population of 11 million individuals were made to pay 300 million dollars for an unworkable security system. Astonishingly, every single Greek citizen could have been given 27 million US Dollars for what it cost to provide security for the Olympics.
Besides the extraordinary cost, C4I was also mired with corruption. Siemens, the subcontractor of SAIC which had been awarded the contract for the super panoptic security system, used C4I as a "jack pot" or "a dummy project" to incur overpayments and bribes, instead of providing a feasible and effective Olympic security system. According to a 2008 Munich court judgment, the Greek branch of the German electronics giant, Siemens Hellas, set aside 2% of the revenue it received from Greek state contracts to pay off both ruling parties in Greece. The conservative New Democracy ( ND) and socialist Panhellenic Socialist Movement (PASOK) benefited as part of a system of bribery that ran years before and well after the Athens Olympics, until 2006, to secure lucrative state contracts.
Yet, C4I Olympic security project is also disturbingly associated with pervasive phone tapping against the Greek government. On February 2 2006, the Greek Government officially announced that the mobile phones of then Greek Prime Minister Kostas Karamanlis, most of his ministers and many other  top government, military and security officials were hacked by an unknown source during the Athens 2004 Olympics and for nearly an entire year after. Our research has led us to adopt the dominant theory on the subject,  that the phone taps were organized by US secret agencies, for reasons related to US Olympic security, the C4I problems and US mistrust of the Greek government and its Olympic security system.
Indeed, the Athens 2004 Olympics had authoritarian effects over the hard-won rights and liberties of the Greek people. Before the Athens 2004 Olympics, U.S. and British pressures and threats to boycott the Games contributed to the Greek Parliament voting in the so-called “anti-terrorist law” 2928/2002 which meant mass surveillance policies and maximum security presence, seriously jeopardizing political rights and freedoms in Greece.  In a country where memories of the last oppressive military dictatorship (1967-1974) are still very much alive, this controversial, so-called “terror law” (tromonomos), has reinforced all surveillance provisions in Greece. The law encourages spying on citizens and provides pecuniary motives for police informers. It also introduced non-jury criminal trials, initiated limited right of appeal, DNA testing without consent, expanding police powers of infiltration and surveillance of groups and individuals, and imposed a penalty of ten-year terms for members of terrorist and crime gangs. Based on this draconian law and the assistance of the British Scotland Yard, the Greek terrorist group November 17 (N17) was arrested and sentenced to jail in 2003. However, this terror-law is a real threat against any kind of political mobilization and reactions against police brutality and state violence.
In addition to the terror-law, another Olympic dowry was largely technological. Over 1,200 sophisticated CCTV systems were posted throughout the Athens metropolitan area and inside Olympic venues during the Games. They were not simple CCTV systems, but were enhanced cameras with speech-recognition software, capable of collecting visual and audible conversations from long distances. The software could transcribe the audible conversations into digital text that was then searched for suspicious patterns along with other electronic communications entering and leaving the area--such as emails and image files.  The Athens 2004 Olympic CCTV system reads, watches, and then synthesizes the data into pre-configured threat designations. The software was capable of understanding Arabic, Farsi and all major European languages, on top of Greek and English. This interoperable network was part of the C4I system. The extraordinary cost of this particular capability pushed the Government to insist on their use in "post-Olympic" contexts, that is, they were used not only for traffic control but also for security and antiterrorism. It wasn't long after the Olympics were over that these CCTV systems monitored political rallies and demonstrations all over the Athens metropolitan area. Political activists started to "blind" the CCTV cameras after it was made evident that they were used to monitor a demonstration by educators in down town Athens during June 2005--almost an entire year after the Olympics.
The Greek Data Protection Authority (DPA) had placed serious restrictions on the functions of the CCTV system and allowed them only to be used for traffic control. This put the Greek DPA in conflict with the Ministry of Public Order and the Greek police HEL.AS. on the matter.  On October 8, 2007  the DPA fined the police 3,000 Euros for using the traffic cameras to monitor a student protest in Athens earlier that year. The DPA also found that 49 of the police cameras still did not operate with privacy protected software that would blur people’s faces. Images from some of the cameras were also kept for more than seven days, further breaking privacy rules. 
On November 19, 2008, the President and five members of the Greek DPA resigned in protest of the Government decision to allow police usage of the CCTV cameras to monitor political rallies and demonstrations during the commemoration of the November 17, 1973 student revolt against the military dictatorship. Early in the following year the government appointed a new DPA, which accepted the use of the CCTV as a broader surveillance tool for protests and demonstrations. In Greece, besides the DPA, senior Greek legal experts, civil liberties organisations, as well as most opposition parties and various other civil society groups have all strongly condemned continued use of the Olympic surveillance cameras after the Games ended. Anti-surveillance resistance against the Olympic CCTV cameras have taken many forms, such as blinding the cameras with black hoods, ripping off their cables, spray painting the CCTV lenses, knocking down the CCTV poles, arson, and so on. Not only young radicals but also mayors and union leaders have blinded police CCTV cameras.
During the last mass rallies in Athens and demonstrations in Constitution Square against the Greek politicians’ corruption, management of the debt crisis, and protest against the severe  austerity measures imposed by IMF and EU, outraged people who gathered daily there and  at Greek squares all over the country entirely disregard police CCTV.  On the other hand, the Greek police, now increasingly modernized and better equipped due to the Olympics, is also reluctant to use the CCTV footage out of fear it will reveal police wrongdoing and brutality, which could then be exposed by the media.
Although Greece is not the UK, Athens is not London and 2004 is not like 2011, we can still spot significant similarities between Athens 2004 and the London 2012 Games. In an era that sees the coupling of a post-9/11 logic of global security with neoliberal economic impacts, Olympic-induced securitization and militarization is also characterizing  the city of London much like it did in Athens as the first post-9/11 summer Olympics.
Despite the financial crisis, costs of London 2012 are estimated to soar above $16.5 billion dollars, surpassing the previous record cost being Athens 2004. I fully agree with what Boyle & Haggerty have previously argued, that the Olympics have become a testing ground for new surveillance technologies produced by powerful private security firms. The firms are able to capitalize on the prestige of their Olympic involvement that helps market their products in wider contexts of "public safety" and "homeland security".
If Athens 2004 was a catalyst for the deployment of the military operated C4I super panopticon, London 2012 plans to deploy second generation electronic surveillance system with martial metropolitan technologies like Automatic Number Plate Recognition (ANPR), Face Recognition   Closed Circuit Television, (FRCCTV) including Unmanned AerialVehicles (UAVs), or 'drones' , which are currently deployed in Afghanistan, to perform a wide range of missions including enhanced day or night surveillance. Also, the highly controversial e-Borders programme will be in use. The e-Borders programme deploys sophisticated computer algorithms and data-mining techniques to track the identities of people flowing across the UK’s borders. Using records of past activity and associations to identify future threats before they materialize, the program might be legitimated and implemented on a permanent basis due to its deployment for Olympics security.
And finally, let me make a general comment on the evaporation of the Olympic spirit. The modern Olympic Games, especially after 9/11, represent nothing of the classic Olympic values. Nationalism, commercialism, doping, urban destruction, and especially securitization over rights and freedoms are now a central feature during and also long after the Games.  The classic Olympic values have clearly been undermined with these new practices associated with the Olympic Games. Securitization of what we might call a "post-9/11 Olympics" in a climate of terrorism and fear, have supplanted Olympic ideals that claim “to promote a better world through sports”. The Olympics have now come to be viewed, not as a pleasant sports event for competition and enjoyment, but as a high-risk security problem that requires its resolution at the expense of democratic freedoms, notably through lucrative corporate profits. The resulting "fortress Olympics" combines extreme securitization with profitable commercialization. As such, it implies the corruption and destruction of bodies and nature, and protracted authoritarian effects versus freedoms and democracy. The contemporary model of Olympics reflecting dominant economic interests tends to become more and more securitized and commercialized, and increasingly dominated by multinational corporations and the homeland security industrial complex. 
Greek people who view their country as the cradle of a classical model of Olympics and Democracy suffer today by the negative outcomes of Athens 2004 as a distorted Olympics and a corrupt democratic system. All those who love real sports and oppose the contemporary security and market-based Olympics should fight together to form a global volunteer movement for the founding of an alternative Olympic Games that would contribute to the construction of a more peaceful and better world.