A "magical" gold ring for scamming people.

Pretty much anything in the PHB. Summon a rope, a cup, etc.

Use to set a trap, cause the object to disappear and the trap goes off (hook holding something heavy up, part of the floor disappears into a pit etc).

Summon clothing on top of what you were wearing before, commit a crime, turn the corner, and will it to cease to exist.

Use it to pass messages (create magical ink, write a message with it and it is gone within the hour).