You may not believe your chances of spotting a flying pig are better than winning the jackpot, but someone has to be the winner, and in true National Lottery glory "It could be you!".

Perhaps it's this lack of confidence in a win that leaves so many unclaimed prizes. Winning tickets must be claimed within 180 days of the draw taking place. If a prize remains unclaimed after that, it is distributed through the Lotto's Good Causes fund.

The highest unclaimed prize distributed this way to date was a winning ticket worth £9,476,995 which expired at Monday January 2 2006. This ticket was the 24th prize in excess of one million pounds to be unclaimed.