The U. S. Postal Service is floating the idea of issuing "forever stamps"—first-class postage that can be purchased now and used at any time in the future.
"You say nothing lasts forever, but this stamp will," [Postal Service spokesman Mark] Saunders said of the forever concept, which some foreign postal administrations, including Britain's and France's, have embraced.I would hope that any great-great-great grandchildren I leave behind would be smart enough to sell those antique stamps on eBay instead of sticking them on envelopes.
"When your great-great-great grandchildren go through your junk drawer at home, when they are excavating your house, they'll say, 'What are these?' -- and they'll still be able to use them." [Link]