I am a sucker for time-travel stories.
I've been intrigued by the concept since I was a kid. Backwards in time; forwards; whatever. The following provides a small sampling of some of my favorite time-travel tales.
The Time-Traveler's Wife by Audrey Niffenegger - This is the class of the group. An extremely well-written and beautiful book. It took the first 50 pages to get used to the time shifting, but after that the story of Clare and Henry really moved me. Henry suffers from Chrono-Displacement Disorder which causes him to move involuntarily through time. It is during one of those time shifts that he meets a young Clare who years later becomes his wife. Don't hold it against the book that book clubs all over the country have this on their reading list. Here.
Time and Again by Jack Finney - I think this was the first time travel novel I ever read. Si goes back to 1880s New York with the help of a mysterious government agency. Finney wrote a couple sequels because people loved the book so much. It's a classic. Here.
To Say Nothing of the Dog by Connie Willis - Maybe it's just me, but a story involving Victorian manners, the bombing of Coventry during WWII, time travel and Jerome K. Jerome's Three Men in a Boat can't miss. I read this in 2001 for the first time and have picked it up three or four times since. It's a comedy science fiction mystery. One of my favorites. Here.
Also....
Shortcut in Time - This is a very low-key novel. An alleyway provides the "gateway" for time travel. But the travel is only 15 minutes back. I enjoyed the concept. Here.
The Diana Gabaldon Outlander series is very popular too. Not a lot of time travel, but good romance. The first one is probably the best. Here.