Megabus.com
Travel from London to select UK cities for only £1 + 50p booking fee.

Megabus travels to the following destinations:
Birmingham, Bournemouth, Brighton, Bristol, Cardiff, Chesterfield, Dundee, Edinburgh, Exeter, Glasgow, Leeds, Leicester, Liverpool, Manchester, Milton Keynes, Oxford, Perth, Plymouth, Portsmouth, Ringwood, Sheffield, Southampton, St Andrews and Swansea.