I've been getting really into random Flash apps/games (mainly culled from MeFi).
PoPoRon is variously described as "Photoshop on acid" and "crazy flying shit". Both are right.
Uncontrol is an awesome collection of interactive Flash animations; generative it seems. Or as the site says: "an interactive exercise that explores the themes of anthropomorphism and kinetics". Be sure to check out games 2 (wurm) and 6 (roach), and the pictures people have sent in under 'draw').