If you liked Surely, you're Joking, Mr Feynman, you may also like

Science:
"Six Easy Pieces" by RPF
"The Character of Physical Law." by RPF
(Actually I think the stuff about symmetry I mentioned in the other post was from this second title instead of the first.)

History:
"Longitude" by Dava Sobel (which we discussed a bit in here some time ago).
This is extremely good and very easy to read.

Autobiographies:
"Enigmas of Chance" by Marc Kac
"Physics and Beyond" by Werner Heisenberg
"What is Life" by Erwin Schroedinger
(One of the SJ Gould books talks a bit about his interaction with his dad, but I don't recall which one ... maybe Panda's Thumb, but I'm not sure.)

(Also there's a great biography of Herman Helmholtz I read way back in junior high, but i can't think of the title, but it was a small orange paperback.)

Fiction:
"Cambridge Quintet," by John Casti, hypothetical dinner and conversation (in the vein CP Snow's The Two Cultures or maybe something like Steve Allen's Meeting of the Minds - in fact, Snow is the host in the story!)

On my list to read
"I am a Mathematician" Norbert Wiener (a friend gave it high ratings)
Oppenheimer's autobiography (forgot the title)
Gödel: A Life of Logic, the Mind, and Mathematics
I, Asimov

k