I just like the way Ubuntu names its versions:
Warty�Warthog
Hoary�Hedgehog
Breezy�Badger
Dapper�Drake
Edgy�Eft
Feisty�Fawn
Gutsy�Gibbon
Hardy�Heron
Intrepid�Ibex
Jaunty�Jackalope
Karmic�Koala
Lucid�Lynx
Maverick�Meerkat
Natty�Narwhal
Oneiric�Ocelot
photo credit: Michael F�tsch