These are some interesting rules from MCell's Weighted Generations.
WtfAngle - a 1/2 dimension CA, occupying primarily one axis of the grid and reactive to nearly any input in interesting, swirling displays. Best with 256 generations.
NW1,NN2,NE1,WW0,ME0,EE0,SW1,SS2,SE1,HI256,RS3,RS4,RS5,RS6,RS8,RB3,RB4,RB5,RB6,RB7,RB8
Jetplanes - the rule where input turns into jet-shaped spaceships and fly away, annihilating against their anti-particles.
NW2,NN2,NE1,WW2,ME0,EE2,SW1,SS2,SE2,HI4,RS2,RS4,RS5,RS6,RB1
I wouldn't mind discussing MCell in this thread either.