Sailing the seas of sulfur hexafluoride [Video]

Watch as an aluminum foil boat floats in a container of sulfur hexaflouride, a gas over five times denser than air. From Neatorama:

Another interesting point is that inhaling this gas will make your voice sound deeper. Sound does not travel as fast in this medium. Helium can transmit sound very rapidly, hence making your voice squeaky.

Link (via Neatorama via Boing Boing)