ChuChu Rocket! was a puzzle game released by Sega's Sonic Team for the Sega Dreamcast in 2000 (1999 in Japan). While it never hit mega-popular status like Tetris or Lumines, it received decent appeal from Sega's faithful.
The point of the game is to guide as many mice towards a goal without being destroyed by a cat. The game also featured a frantic 4-player mode. You could even go online via Seganet and play against a far-away friend or stranger.
But with the death of the Dreamcast pretty much destroyed the series' potential. Besides a GBA version in 2001, no real sequel has been produced.
But Sega finally remade the game for the mobile market on iOS and Android. I really hope Sega decides to release it on Xbox Live Arcade since I really want to give this series a try. Never had the GBA version, and my brother never had the game on his Dreamcast.