Loadstone: A stone which appears to be a Luckstone until the owner is being pursued by hostile enemies/monsters. In the case of such pursuit the Loadstone slows his movement by 50%.
This doesn't kill a player, it just adds a complication. I can see this leading to player death, but also I can see it leading to a hilarious panic along the way. By the way, these are way more common than Luckstones, their non-cursed counterpart.
Boots of Dancing: These boots appear to be any of the others listed before them, and they will continue to so function until their wearer is in a situation where an enemy is in pursuit with intent to kill or some similar situation. When this happens the boots cause the feet of the wearer to dance a jig, soft shoe, tap, and an occasional Shuffle off to Buffalo. Naturally, he is then unable to flee or otherwise escape.
Exactly the same gimmick as the Loadstone. I'm sure the "shuffle off to Buffalo" gag got a few chuckles in the 70s.
Horn of Bubbles: This device exactly resembles a Horn of Valhalla, but when it is sounded it will bring forth a cloud of bubbles which surround its holder, completely obscuring his vision for 4-12 turns.
The Horn of Bubbles is one of the few items that doesn't either kill you outright or necessitate a Remove Curse. It just waits until you are in a situation dire enough for you to need the help of berserker warriors, and instead of aid, you get covered with comical soap. A++! Would sound horn again!
Girdle of Femininity/Masculinity: Although this item appears to be a Girdle of Giant Strength, as soon as it is worn it changes the sex of its wearer. It can be removed only with a Wish
Ah, the Girdle of Femininity/Masculinity, introducing hundreds of 70s teens to the ultimate horror: playing a female character!
OK, not all these cursed items are great. But at least they don't arbitrarily kill you!