I've just come across a this list of Ingredients for Serious Thought by Lance Fortnow, a researcher in computational complexity. Although I don't claim to be capable of proving even the simplest theorems in complexity theory, these are exactly the conditions I need to get in the 'zone', especially 8 and 12: I get fantastically productive on the train and late at night. Now I wonder what a late night train journey might conjure up...

Interesting weblog by the way. One to add alongside Jacques Distler