Relative sizes of 88 largest objects in the solar system
Found this by way of Cosmic Variance: it's a figure of the 88 largest objects in the solar system. I know I've come down on the Pluto issue before: I argued for the anti-Pluto view that the IAU eventually adopted (it's so rare for me to actually be on the winning side of anything). This picture shows were Pluto and other large but not large objects fall. I still stand by my original view, but this picture does show that coming up with a hard cutoff point is very, very difficult at best; it's almost a smooth gradation of diameters from Earth downward, though between Mars and Eris, Pluto, etc are quite a few large moons.
At the very least, it's a pretty picture.