One-Punch any entity while in creative mode, as long as you're not holding a weapon.
Awesome logo by @oliwoli, a big thank you!
Since 1.8 there is now a creativeonepunch.json config file with:
damage: the damage dealt, defaults to 9999
forceKill: bypasses any invulnerability checks, defaults to false
requireSneak: whether One-Punching only works when sneaking, defaults to false
