Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
There are more than 270 people cryogenically frozen in the hope that one day the technology will exist that can revive them and extend their lives.
13
One cubic foot of gold weighs more than 1,200 pounds!
78
Marie Curie, the Nobel prize winning scientist who discovered radium, died of radiation poisoning.
57
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5