Time travel stories can be mind-bending and thrilling. To Say Nothing of the Dog by Connie Willis shows they can also be funny.
This was my first time reading Willis. I had heard of her, both as a frequent Hugo and Nebula winner but also as an example of a humorous SF writer. I don't think there's enough humorous science fiction out there, so I was keen to check this out.
The basic idea: Oxford historians in the 2050's use time travel to go back to a variety of eras. They can't take any objects back with them or make any major changes to the timeline, but they are able to interact with and observe the past. Given these limitations, time travel has no real commercial applications and is left mainly to historians and wealthy eccentrics. The main character Ned Henry has done several too many "drops" into the past, resulting in excessive "time lag" (sort of like jet lag but funnier). To recuperate and to avoid the overbearing benefactor of the time travel program, Ned goes back to Victorian England in 1888. Of course, it turns out he's actually been sent on a mission to locate a certain artifact, a hideous Victorian monstrosity called the Bishop's bird stump, which they need to replicate as part of the rebuilding of the Coventry Cathedral that was destroyed in WWII. Hijinks and hilarity (and even a bit of romance) ensue.