Not sure where to post it, I don't want to bump really old threads so I'll ask here:
at the initiative of SAoVQ, we are writing a small guide to anonymous boards on a wiki. It's not very good right now, but we've just started: http://tanasinn.info/wiki/A_Guide_to_Anonymous_Boards

On the part about tripcodes, I talked out of my ass about choosing a good tripcode. Could someone who actually understands well the CPU cost of cracking various tripcodes help us to provide an easy rule to follow for choosing something uncrackable?