Dream Key Beta
Chu Chu Rocket has a beta of Sega's new DC browser DreamKey built in to view the Chu Chu Rocket webpage, Dreamkey is faster then the browser that came with the DC and you can listen to WAV and MIDI sounds and download them onto your VMU.
Go to the HOMEPAGE option and anywhere on the Chu Chu Rocket webpage hold down Ctrl and press O on you Dreamcast keyboard, now you can go to any page you want!
NOTE: there is no way to view other sites though Chu Chu Rocket without a keyboard.
Submitted by Spamcan
Unlock Chao in the game
Beat all 25 levels in Stage Challenge Mode to have the Chao from Sonic Adventure replace the Mice.
Submitted by Super Carle
Unlock NiGHTopians in Puzzle mode
Complete all 25 Mania puzzles.
The NiGHTopians are the "A-Life" creatures from the classic Saturn game "NiGHTS".
Unlock hard mode
Complete all 25 Normal mode puzzles.
Unlock mania mode
Complete all 25 Special mode puzzles.
Unlock special mode
Complete all 25 Hard mode puzzles.