O-D-C on 28 April 2008
Out of all the ones I own for handhelds I would have to say the NINTENDO DS mostly due to the fact that it's a breath of fresh air. I loved GB-GBC-GBA but the DS is so different from the Game Boy line that it tajes the cake.
As for consoles I would say the NINTENDO GAMECUBE, amazing controller, great graphics and some of my favorite games ever are on the Gamecube, games like:
Super Smash Bros. Melee
Paper Mario: The Thousand Year Door
Super Mario Sunshine
The Legend Of Zelda: The Wind Waker
Metroid Prime
Star Fox: Adventures
Battalion Wars
Resident Evil 4
Star Wars: Rogue Squadron II: Rogue Leader
to name a few.
HONORABLE MENTION: Virtual Boy and Game & Watch (Zelda)
Real conversation starters.