Ring of Eternal Suffering (3.5e Equipment)
From D&D Wiki
This ring has no known design other than that of a ring. When worn it cannot be taken off for the ring becomes one with the wearer. The ring can leave a large scar on the finger when it was put on, a discoloration, and/or a lump from the ring. The ring then causes pain at random times with random intensity and for a random length of time.
 DM notes
The time between the effects and damages resulting from the effects are totally up to you. The ring can not cause death, but can cause temporary paralysis in part of the body or in total.
Other notes Feel free to edit this and add anything that I missed