I understand that Brian is a sucker for time travel novels. So you must know Jack Finney's Time After Time? (Time travel in another medium: Ever see the movie "The Final Countdown"?)
Wow...this is question #500!!! I am indeed a sucker for time travel novels and I love both 'Time after Time' and 'Time and Again'...Finney did a masterful job on both of them. I haven't seen The Final Countdown, but I'll look into it.