The London Classic is an "urban cyclosportive" around London that takes place on Sunday 1st April 2012. You can do it on a road bike which makes the cobbled sections fun. Registration is free but donations are collected for the Evelina Children’s hospital at Guys and St Thomas’. See here for registration which just opened today and further details. It's limited to 300 entries. I did it last year and it was good fun. Going again this year, so if you're going let me know and we can meet up. Face.