In 2007, the government agreed a 9.3 billion pound budget for the London 2012 Olympics. Rather surprisingly, they've just announced that they are now "increasingly certain" of delivering the Games for less than 9 billion pounds -- considerably under budget.

So where has that 9 billion pounds been spent, and which companies have benefited the most? What's more, who will benefit from the consumer expenditure generated by the Games?

A search through the last year's company announcements using keywords like "London 2012" reveals that all sorts of companies are making vague claims of expected trading improvements during the Olympic period -- but who will really see enough of a boost to affect their bottom line and, more importantly, won't experience a corresponding downturn afterwards?

On your marks!
I've listed some of the companies with a reasonable claim to an Olympic boost below. They range from FTSE 100 giants to AIM-listed tiddlers, so the impact of the Olympics on each company could vary widely.

One of the biggest companies listed below is a rare U.K. investment for the world's third-richest man, billionaire investor Warren Buffett. Earlier this year, he increased his holding in this company to more than 5% and I'm very happy to hold it in my portfolio, too. If you'd like to find out the name of the company, the price Buffett paid, and what its big attractions are, then download this free Fool report.

Get set!
Believe it or not, I've whittled this longish list down from a much longer list of possible contenders. At the end, I've selected two of the companies listed below as possible gold medal winners for Olympic investors -- based not only on their Olympic prospects but also on wider operations.

Sector

Companies

Food & Drug Retailers Tesco (OTC: TSCDY), Sainsbury, Wm Morrison Supermarkets -- all expected to benefit from a temporary lift in Sunday trading restrictions. Elsewhere, you have Sports Direct International, JJB Sports and Greggs.
Media Overpaid advertising giant WPP and talkSPORT radio operator UTV Media both expect a surge in advertising revenues.
Support Services G4S (LSE: GFS.L) has a contentious 283 million pound deal to provide security at the Games. Serco, Aggreko and Atkins also expect benefits.
Telecoms Vodafone and BT Group should see a short-term lift. AIM minnow Pinnacle Technology Group (LSE: PINN.L) has an important contract to provide telecoms services to overseas broadcasters at the Games.
Construction & Materials Balfour Beatty (LSE: BBY.L) has both pre- and post-Games contracts.
Travel & Leisure, Leisure Goods Last year, Greene King acquired Capital Pubs, giving it a total of 250 pubs within Greater London. Passenger numbers should rise for transport operators Go-Ahead and FirstGroup, while First is also providing additional spectator services. Finally, collectables manufacturer Hornby expects sales of its London 2012 merchandise to make a strong contribution to its profits.

Go!
My own two tips for Olympic glory are Balfour Beatty and Pinnacle Technology Group, but if you'd like some tips from the Fool's in-house team of analysts, I'd recommend this report, "Top Sectors of 2012." It covers three key sectors with several specific tips for each.

Balfour Beatty
Infrastructure specialist Balfour Beatty constructed the Aquatics Centre for the games and recently announced a 50 million pound, 10-year deal to run the Queen Elizabeth Olympic Park after the Games.

As my Foolish colleague Tony Luckett highlighted back in January, Balfour Beatty increased its dividend every year through the recession and currently trades on a price-to-earnings ratio of only 7.9, with a handsome dividend yield of 4.9%. Adding icing to an already attractive cake, it announced a 300 million pound Highways Agency contract yesterday.

Pinnacle Technology Group
My second tip is a micro-cap punt that is growing strongly, and I believe it could be approaching a breakthrough into profitability. As I mentioned above, Pinnacle Technology Group is providing a range of telecoms services to BBC International at the Games, a role it also performed at the Royal Wedding last year.

Behind this lies substantial growth -- its customer base has grown by 250% over the last year, and it recently reported Q1 revenues up 175% on the same period last year. Currently trading at 0.33p per share, it might be worth a look if you're a small-cap investor.

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