I just finished my Smiley-O-Mat - it's a tin-box with 3 turning knobs that allows you to controll the appearence of a smiley. With 3 simple turns I can now tell your co-workers, familymembers, ... how you feel at the moment and if it is wise to talk to me right now 
my blog post contains the processing and the arduino code
This is what the controller looks like
and this are some of my smileys
Hi! Very nice 
But how many smileys can you exactly create?
I love this! I need one to point toward my kids.
I think everyone in the world should have one of these in a hat with a revolving marquee.
@Tijnie
20 eyebrow positions
50 mouth positions
512 shades of color
makes 512000 different smileys
Throw this on a 320x240 lcd, all in one little package. Or even one of those 8x8 LED modules.
Quite some faces(Y)
that's fun, thank you.
It also has law enforcement applications. if you get mugged by a smiley you can use this to do a really good likeness.
I wonder actually if you could adapt it to do human faces with three knobs - general shape of face, hair, expression?