Hardware:
GBA- Complete USA Blue SP
GB- Loose GameBoy Light (Tezuka Osamu World Shop Clear Red version)
Software (USA and complete unless noted otherwise):
GBA:
Wario Ware
Advance Wars
Lunar Legend
King of Fighters EX 2
JP Super Mario Advance
JP Minna De Puyo Puyo (AKA Puyo Pop)
Gradius (loose)
Arcade Advanced (loose)
GB (Loose and USA unless noted otherwise):
Pokemon Yellow
Donkey Kong GB
Bomberman GB
GB camera (green, with manual)
Tetris
Super RC Pro Am
Operation C
Kirby's Star Stacker
Game and Watch Gallery 2
Super Mario Land 2
JP Dragonball Z: Gokou Hishouden (complete)
JP Puyo Puyo Tsuu/2 (complete)
JP Pocket Monster Cards GB (complete, AKA Pokemon Trading Card Game GB)
"Super 32-in-1" (HK multicart with Flipull, JP Soukoban 2 (Boxxle 2), Duck Tales 2, Battle City, Side Pocket, Dr. Mario)
So that's 8 for GBA, and 14 for GB.
Favorites (doesn't mean I hate the other games, but these are the games I enjoy the most):
GBA:
KOF EX 2 (duhh!)
Minnna de Puyo Puyo
Wario Ware
GB:
Kirby's Star Stacker
Puyo Puyo 2
G&W Gallery
Operation C
Bomberman GB
Donkey Kong GB (aaugh I'm stuck in this game

)
Tetris
SML 2 (stuck on Wario's Castle

)
I love the GB Light, it gets good batter life even! Shame it never came stateside

.
The SP is cool too
