Favorite: 1969 (or was it a '68?) Dodge Dart GTS (340 hi-po V-8). Handled great for such a big car and had more power than I knew what to do with.
Honorable Mentions: My first car. 1964.5 Ford Mustang coupe. All the fenders were rusted out and the paint was terrible but it had a 200 Sprint straight-6 and a toploader transmission. And best of all, it was MINE!
Mom's 1970 Buick Electra 225 with 455 V-8 and posi rearend that I got to drive when I was in HS. Drove like a boat but had lots of power. And a HUGE backseat. Look up "gas hog" in the dictionary and there will be a picture of that car.
Least Favorite: early-'90s Dodge Spirit. Nice family car, so it fit my needs at the time, but no power and the suspension was terrible.