Perhaps I am looking in the wrong community, but I expected Chao to be a popular topic here. Oh well.
For those who don't know, Chao Garden is a side game in 'Sonic Adventure' and 'Sonic Adventure 2' for the Sega Dreamcast, and 'Sonic Adventure DX' and 'Sonic Adventure 2: Battle' for the Nintendo GameCube. In each game you have three 'Gardens' where you can keep a maximum of 8 artificial lifeforms called Chao per Garden. Based on how you raise your Chao, there's more than 50 possible outcomes!
Each garden starts with two normal eggs, but you can also buy different coloured eggs from the in-game market to hatch into coloured Chao.
Once they reach a certain age, they can mate with each other. Mating certain colours together will result in some very interesting patterns, including an Invisible Chao!
A website with lots of pictures of different Chao ishttp://www.yamipoli.com/chaobeach/
Information on raising Chao (mostly for Sonic Adventure 2) can be found athttp://www.chaotropolis.sstrike.net/
I am currently raising two Chao on Sonic Adventure DX (my favourite version). One is a normal Chao named Garrett and the other is a Pink Chao named Stacey. I am raising them to hopefully breed a Pink & Normal Two-Tone Chao.