This Google video puts a good dozen of the known planets into a truly awesome perspective. As noted on digg, if you take the distance between the Earth and Sun (149,000,000km) and multiply it by 25, you get approximately the diameter of VV Cephei (3,676,200,000km). That’s just unreal.

This image seems to be slightly more accurate in it’s proportions, however the true scale of it is somewhat lost due to its static nature.