and do you use different picks for different guitars? I ask because I can only play with my favoured type of pick. I mean, I can play with any pick but I find that I'm incredibly cack handed if I don't play with the particular pick I like. Even if it's the same brand but slightly thicker/thinner.

I use these picks: http://tinyurl.com/bu59oj

I buy them from the same guitar shop I've always bought them from, and the woman who owns the place said that it's not uncommon for people who learn to play with these picks to only be able to play competently with them (due to the shape, or something).

Anyway, interesting thread, huh?