I never really watched the Quantum Leap series, but I know a little about it from reading Mary Jean Holmes fics. Apparently, the latter seasons suggest that Sam Beckett physically travels through time - as well as mentally. For the longest time, though, I guess it was suggested that Sam Backett only mentally travels through times.
I've always been interested in body switching movies, like Freaky Friday and Vice Versa - although, it's not quite as interesting as time travel. It's very interesting, though, when you combine the two.
Peggy Sue Got Married and 13 Going On 30 are both like that, even though it's becoming you at a different age. In His Father's Shoes has a son becoming his father, at his age. I also saw a movie a long time ago, about a girl who faints in the barn - and she becomes her grandaunt, or something. I can't remember what it's called, though.
Do you know of any other movies that are like that?