THE SILOAM TUNNEL INSCRIPTION has been requested back from Turkey by the Mayor of Jerusalem:

Jerusalem Seeks Return of Ancient Tablet
By MATTI FRIEDMAN
The Associated Press
Friday, July 13, 2007; 7:54 AM

JERUSALEM -- Jerusalem's mayor has asked the Turkish government to return a 2,700-year-old tablet uncovered in an ancient subterranean passage in the city, sugggesting that it could be a "gesture of goodwill" between allies.

Known as the Siloam inscription, the tablet was found in a tunnel hewed to channel water from a spring outside Jerusalem's walls into the city around 700 B.C. _ a project mentioned in the Old Testament's Book of Chronicles. It was discovered in 1880 and taken by the Holy Land's Ottoman rulers to Istanbul, where it is now in the collection of the Istanbul Archaeology Museum.

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There's more on the Siloam Tunnel Inscription here [bad link now fixed]. The project is mentioned in 2 Kings as well.

UPDATE (16 July): More here.

UPDATE (17 July): More here.