Here's a little fun mutator with no gameplay impact whatsoever:
Headshot View brings you the old UT feature of viewing through your player's eyes after dying from a headshot. "Headshot" in this sense not only is a fatal sniper or LG hit to the head, but also getting run over by a Manta. (The damage type is configured that way, there's just no logic to announce the headshot. The Wormbot IRC Reporter also picks it up this way.)