It's not just the Egyptians.
Peru is demanding that Yale University return an entire collection of antiquities excavated at Machu Picchu in 1912 that it insists was deposited at Yale only as a loan.
http://www.stltoday.com/stltoday/news/stories.nsf/stlouiscitycounty/story/2E25424B3CC6C68E8625712000813AC6?OpenDocument&highlight=2%2C%22antiquities%22
Greece and Turkey also claim that U.S. museums hold artifacts looted from their soil.
http://www.bloomberg.com/apps/news?pid=10000088&sid=a_6ssJtZ2pt0&refer=culture
Ethiopia wanted obelisk returned to it from Italy. They got it back, but it is still sitting pieces.
http://www.iol.co.za/index.php?set_id=1&click_id=31&art_id=vn20060227011059174C927322