White elephant

A white elephant is a possession which its owner cannot dispose of and whose cost, particularly that of maintenance, is out of proportion to its usefulness. The term derives from the story that the kings of Siam, now Thailand, were accustomed to make a present of one of these animals to courtiers who had rendered themselves obnoxious in order to ruin the recipient by the cost of its maintenance. In modern usage, it is an object, scheme, business venture, facility, etc., considered without use or value.

http://en.wikipedia.org/wiki/White_elephant