Let me see if I can post this, which idea I got from Walt Crawford.
create your own visited states map
or check out these Google Hacks.
There is certainly a pattern, and someday, I need to do the Northwestern part of the country. I'd also like to visit Michigan's U.P. (which is colored in because of my many visits to the "hand" of Michigan). I'll even claim extensive travel in the six New England states, New York, New Jersey, Pennsylvania, and Maryland. I've also seen a great deal of Illinois, Iowa, Arizona, and New Mexico. Many of the other have been either plane hops in and out (Louisiana) or "drive throughs" on the Interstate.
Hmmm. No I'll have to do the world map.