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White Elephant from WikiPedia:

A white elephant is a valuable possession of which its owner cannot dispose and whose cost (particularly cost of upkeep) is out of proportion to its usefulness or worth.

The term derives from the sacred white elephants kept by Southeast Asian monarchs in Burma, Thailand, Laos and Cambodia. To possess a white elephant was regarded (and is still regarded in Thailand and Burma) as a sign that the monarch reigned with justice and power, and that the kingdom was blessed with peace and prosperity. The tradition derives from tales which associate a white elephant with the birth of Buddha, as his mother was reputed to have dreamed of a white elephant presenting her with a lotus flower, a symbol of wisdom and purity, on the eve of giving birth. Because the animals were considered sacred and laws protected them from labor, receiving a gift of a white elephant from a monarch was simultaneously, both a blessing and a curse: a blessing because the animal was sacred and a sign of the monarch's favour, and a curse because the animal had to be retained and could not be put to much practical use, at least to offset the cost of maintaining it.

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