mycoted is a site i have just discovered. this is the blurb...
Mycoted is dedicated to improving Creativity and Innovation for solving problems worldwide, with that in mind, we provide a central repository for Creativity and Innovation on the Internet as a summary of tools, techniques, mind exercises, puzzles, book reviews etc, that is open to all - and can be written by all.
there's a pretty impressive A-Z of creativity techniques, some of which i've seen before (random words, wishing, six hat thinking etc) and others i haven't. leave a comment if you have tried any that worked well.
if you like lateral thinking which is always good for stretching the mind there is also a section of puzzles . i find it amazing that even though i know there's a catch that's obvious in hindsight i often can't spot it!