[withad]

I recall the Game Boy Colour doing something similar, though it apparently had its own system - http://en.wikipedia.org/wiki/Game_Boy_Color#Color_palettes_u....

And now I'm trying to remember what the Game Boy Tower in Pokemon Stadium made the games look like...

[fuzzywalrus]

If I recall correctly the GameBoy Color could only assign sprites 3 colors.

What's interesting is Nintendo also made the GameCube GameBoy Advance attachment much later