Cursed items are annoying... but that's by design. That got me thinking about which cursed item... technically caused the least amount of troubles for characters.
After some reading, the Ring of Truth doesn't seem that bad.
1) You still can "ignore" the answer. Answering "I don't know" when you actually don't know the answer won't get you in trouble.
2) It's a Will DC 20 save to refuse answering. We're not talking about such a big deal here.
3) Questions HAVE to be directed at you. You don't start answering every question you hear whether or not you get asked.
Oh yeah, one more thing, the Vow of Truth is now "justified" when you wear this ring :P
Another example is the Girdle of Opposite Gender... which seems more like a prank-like item than anything else. You changed gender, so what? Mecanically, there's almost nothing related to gender. I haven't specific spells, ietms, feats, prestige classes, archetypes and whatnot where being male or female is required. In fact, there's a little loophole here: what if the target DOESN'T have gender? A male changeling doesn't exist, so how does the cursed belt work on her?
So yeah, the gender-switching belt doesn't seem that harmful, compared to other items. Changing alignment can screw your character up, but gender? I doubt it.