Royal Mint explains offside rule on commemorative coin

With the 2012 Summer Olympics in London approaching, the Royal Mint has produced perhaps the most useful commemorative coins of all time. The genius design for the football coin -- created by a competition winner -- features a diagram on the back that finally illustrates the offside rule, which has the ability to confuse new and old fans alike, in coin form.

RoyalMint.com explains:

In January 2009 the Royal Mint launched its biggest ever competition, inviting the British public to design a series of new 50p coins. Thousands of excellent designs were received from all over the UK, featuring all 29 sports of the 2012 Olympic and Paralympic Games. The best designs were selected and now they've been made into coins for you to collect as lasting mementoes of London 2012.

The Football 50p coin, designed by Neil Wolfson, comes in a fun and vibrant pack, making the London 2012 Sports Collection a special set of coins for all the family.

Though this commemorative coin has great upside as both a handy educational tool and usable currency, linesmen may want to start wearing helmets. It probably won't be long until fans try to improve a linesman's understanding of the rule by forcibly implanting one of these coins in his skull after a bad offside call.