Pun-Pun
Pun-Pun is the god of munchkinry. The ultimate example of "breaking the system" in 3.5, Pun-Pun is an ECL 6 kobold character build that can cast every spell and psionic power at will, has infinite stats (and therefore infinite HP), and has a divine rank of 30. While the original version of Pun-Pun was a 12th level psion, the most recent shattering of the system uses only standard divine/arcane magic and setting-specific splatbook feats.
Pun-Pun will bitch slap you for 1dAssload damage. Do not fuck with Pun-Pun.