[*]Mehrunes Razor - Seems underpowered compared to other games. I think I've only had a couple of KO's with it despite using it the entire DB questline.
[*]Mace of Molag-Bal - Pretty lame in my opinion, though I'm no mace user.
[*]Spellbreaker - I guess it's decent in theory, but I stashed it away and never took it out again.
[*]Dawnbreaker - Pretty sure I stashed it in some drawer, and then accidentally sold it when I was doing some spring cleaning and just looked at the base damage. Meh.
[*]Sanguine Rose - The quest was fun and all, but the summon dremora for 60 seconds is pretty useless to me with 100 conjuration.