Flubba has released a new Colecovision Emulator for the GBA Micro/SP (also works on Nintendo DS and the Gamecube Gameboy Player)

Heres the info:

I spent a couple of days hacking SMSAdvance into a Coleco emulator.
I also hex hacked the builder so watch out for falling debris.
Some problems do exist, some games crash/freeze others are missing correct controls.

Download Here --> http://gbaemu.dcemu.co.uk/smsadvance.shtml