Well I don't remember exactly all the enchantments I put on it for I haven't played the game for a long time, but In Morrowind, I have a battle axe with tons of spells encahnted on it...I think it has fire, frost, and poison, as well as soul trap, levitate, speed, jump, etc etc, shield, invisibility, anyways, yeah I have this thing tricked out pretty bad. It looks frickin awesome when you use it, 1 hit kills, I'm basically invincible, which is nice.
Second to that would have to be the sniper rifle in any game, find a good hiding spot up high and shoot away. Of course, it works even better with a modded version of a game, rapid fire missiles from a sniper rifle is a pretty sweet site, tough to beat as long as you don't get kicked off the server. (No, I don't use modded weapons in games online, cheating, but they still look pretty cool if you do)