Today we read that the cost of the 2012 London Olympics is expected to be in the order of £9 billion, four times the estimate at the time the location of the games was "won" by London's Olympic Committee with some help from Tony Blair. Given that there are 5 more years left to run, it is very probable that £9 billion may not be the final amount.
Turn the clocks back to 1984 and the Los Angeles Olympics. By using existing facilities with just the right level of upgrading, Los Angeles hosted a memorable Games with the exceptional extra - they made $250 million profit! The profit went to support youth sport across the USA. The man in charge was Peter Ueberroth. London needs to call him and find out how it was done!