Linux distribution release code names

Debian

buzz
rex
bo
hamm
slink
potato
woody
sarge
etch
lenny
squeeze

Redhat

RHL at Wikipedia

Mother's Day
Picasso
Colgate
Vanderbilt
Biltmore
Hurricane
Manhattan
Apollo
Hedwig
Cartman
Zoot
Guinness
Seawolf
Enigma
Valhala
Psyche
Shrike

Redhat Enterprise Linux

RHEL at wikipedia

Zoot
Pensacola
Panama
Taroon
Nahant
Tikanga

Redhat Fedora

Fedora releases on wikipedia

Yarrow
Tettnang
Heidelberg
Stentz
Bordeaux
Zod
Moonshine
Werewolf
Sulphur
Cambridge
Leonidas
Constantine
Goddard

The Truth Behind Redhat/Fedora names - more comprehensive list.

SuSE

Uses numbering only?