The Planetary Society has some amazing images & animations of Earth taken by planetary spacecraft.

My favourite at the moment has to be the image of Earth from the surface of Mars, taken by the Spirit rover in 2004 and the first image taken from the surface of an object beyond the moon.

Shades of the Total Perspective Vortex, for those HHGTTG fans out there.

Speaking of which, Paulo Ang has a rather wonderful Flash animation entitled “The Total Perspective Vortex” which makes powerful use of planetary and astronomical imagery alongside music and a liberal smattering of Hitch Hikers quotes.