Allows the wearer of this ring to choose the destination of any teleport effect that targets the wearer. This works if you step on a trap, cast the spell/wand on yourself, etc. You can go 4 floors above or below you, and horizontal distance does not seem to be restricted. Targeting is done by guiding a purple spell effect cloud around the screen until you click on the spot you like.
This effect is useful for scouting and exploring as you can see everything at a location before actually going there and reveal the map as well.
Fountain Wishing: Must drop between 1000-3000 gold into a fountain to wish for this item (still narrowing it down)
Combine this ring with the Teleport Away spell or wand of teleport to travel quickly from floor to floor.