This one is an oldie, but I'm a sucker for NASA's rocket comparison graphics. I cleaned the one above, which I took from this PDF overview of NASA's Space Launch System by the Marshall Space Center. I just wish someone made a high quality vector file to print out in giant format.
DISCUSSION
This makes me wonder if my dad still has some of his old Atlas Centaur stuff left over from his days at Lockheed-Martin; he used to bring home posters of the rockets that he was working on, and I have quite a few DVDs of rocket launches that he gave me.