I've been trying to think of a good X topic since the start but I've come up with nothing. So let's have a little fun instead, and as Dungeon Masters what could be more fun than a peculiar cursed item. This time we have the accursed Xylophone, stashed in any decent horde it stands out from the rest of the mundane treasure. This Xylophone has absolutely zero effect unless someone decides to play it using the mallets attached to its frame of petrified wood. Once they do they'll be in for a surprise.
No. Appearing: 1
Armor Class: 9
Special Attack: Curse of Perfect Pitch, Curse of Perfect Melody
Magic Resistance: Immune to all magical effects excluding dispel magic, disjunction and flame or wood properties.
After the PC plays a note, any note, they are going to make a saving throw the next time they sleep. Save vs Spell or an appropriate Save regarding Mental Compulsions. The PC will begin to dream of the Xylophone and of the note(s) they played. They will feel drawn to it, to continue playing it until they are able to hit the right note. This is the curse of the Perfect Pitch. The problem is this xylophone of petrified wood is incapable of projecting the right pitch. Try as they might the PC's will never be able to hit that perfect pitch. This means they will be continuously missing sleep and possibly losing their own personal free time to this accursed instrument. Bonus points if you have them sleepwalk (sleep perform I guess) and the other members of the party find out.
After the Cursed Character has made enough sounds they will begin forming melodies. Some they may have heard in their past or on the road, others completely of their own volition. They will get to experience first hand the inspiration of the musician and the agony that comes with failure just short of success. Try as they might they can never get the song to sound just right, always seeking perfection they continually end with flawed results. The compulsion begins to dominate their mind and if they are unable to break free of it they will become a slave to the Xylophone, always trying for that perfect musical moment and never achieving it. Saving Throws can be allowed after extended periods of time (weeks that bleed into months and years) or for when other PC's or significant others try to convince them to drop this habit. Remove Curse from either a spell or a mystically endowed clergy has no effect as the compulsion comes from within the character and they cannot remove it with wanting to do so. So long as they are unable to hit the right note and form the right melody they are unable to form the desire to stop playing it.