I LOVE roadtripping (as I am sure I have mentioned MANY times here
) In the past 5 years I have driven Winnipeg to LA twice (once down to Chicago and along Route 66, once to Seattle and down the coast), twice to Florida (once to Kissimmee, once right down to Miami for a cruise) and a big Eastern seaboard trip that took me through Nashville, Pittsburgh, Philadelphia, Washington and New York).
Over 30K and loved every second. I can't wait for Europe, I will be a sightseeing beast. Only thing is you want to go for like 2 months so you can really see some stuff.