[SixOfSpades]

A lot of the "useless" items are actually quite handy, in the right circumstances. Take the Claw of Kazgaroth: Let's say you're building a Fighter->Cleric, and you roll the guy to have 18 CON. Get the Fighter level you want, Dual to Cleric, and then put on the Claw. Clerics don't need any more than 16 CON, so the Claw's -2 to CON is negated, and Clerics also have very good Saves vs. Death, erasing the Claw's other drawback. So, you have a better AC and better Saving Throws, at the cost of your character looking all blurry.

Potions of Mind Focusing: Get your INT up to 25, and your chance to scribe a spell scroll is 150%. Yowza. Kinda justifies building a Mage with only 9 INT. Also, no matter what class you are, a +3 bonus to DEX pretty much guarantees a +1 (at least) AC bonus.

Useless stuff:
There's a spell that's even worse than Infravision: Magic Stone. Spend a round casting a spell, and be rewarded with--a sling bullet. Oh, wow, hot damn.

I've never even tried the Horn of Kazgaroth.

The Longtooth dagger--at that point in the game, who the hell cares? And how's it supposed to be better than the Dagger of Venom? Maybe if you had 2 Druids in your party.....

Clubs--Let's hear it for the ONLY WEAPON IN THE GAME that does NOT come in an enchanted version, not even +1.

Bards

Boots of the North--actually, they're not THAT useless....they come in quite handy when all those Mages cast Cone of Cold and Ice Storm on you.....wait a minute....

Wand of Polymorphing--boy, this thing really works like a charm, doesn't it?