Helm of Draining

Grants the intrinsic Magic Drained, which pours your mana out on the dungeon floor.

This is actually faintly useful when following H'ruth (or Xom in a bloodthirsty mood), as it can prevent you from accidentally casting spells....

Oh, who are we kidding, this thing purely sucks, especially when it's cursed. (Besides the immediate problem, futilely regenerating all that mana really boosts your appetite!)