Anyone who has ever studied law, no matter how much they have forgotten, will always remember two or three cases. One of these is Cahill v Carbolic Smoke Ball Company (1896) which established an important point of Contract Law. Basically, the company advertised their product claiming that it was a sure guarantee against catching 'flu and offered £100 (£10,000 in today's money) to anyone who caught 'flu after using it. Mrs Cahill bought one then later contracted 'flu. On her recovery she claimed the £100. The company refused to pay up, claiming it was only an advertising gimmick. The matter went all the way to the House of Lords, where Mrs Cahill won her case. Advertisers, beware.