No offense to Charlie Brown himself, but the Peanuts protagonist's super-smart black-and-white beagle Snoopy is probably the legendary comic strip's most famous and beloved character. He's appeared in the funny papers for well over a half-century and makes a healthy sum on the side shilling MetLife insurance.
After a few years on all fours, Snoopy now walks on two legs and communicates his thoughts through thought balloons, and via his own quirky shrieks and whimpers on the Peanuts animated television specials.