isn't it totally annoying when you have a great design idea then forget it?
to counter this i try to write down all my ideas in a notepad but this often backfires. for example my current list reads:

cloudbusting
lucky
fibonacci
atoms - very small things
stitched up
folded banknote
oil rainbow
elephant juice / isle of view
flip flop flyin'
stag on wall

i can't for the life of me remember what embryonic ideas 'lucky' or 'atoms' refer to. i think the next ones to be developed will be cloudbusting and elephant juice.