Something which looks great initially, but, on closer inspection, reveals itself to be total shit. Fools gold.

Etymology:

From ZEBU - a jowly cow-like creature from South America (that bears a passing resemblance to Rupert Murdoch) whose meat is often passed off as 'British steak' in pubs and restaurants - and BULLION - Money, gold, shekels, loot etc.
e.g. "It looked good on ebay, but it turned out I was chasing Zebullion"
by Delmore October 13, 2009
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