What is your favorite book? Why is it it your favorite? tell how it touched you or made you better as a person? Or learned some valuable lessons from? :)

Catch-22. It taught me many things, such as cynicism, and to never get into a war with Italy.

Stranger in a Strange Land still stays with me,but to single out any one novel is possibly a futile exercise since the range is so wide.
The Whistle-Blower....any Steinbeck..Hawaii and most of the other Micheners...Foundation Trilogy...all five books in the Hitch-Hikers Guide to the Galaxy trilogy...

I have a full set of Harry Potter.
I am reading Order of Pheonix.

Heavens to Betsy! I completely forgot to mention "The Devil's Dictionary," by Ambrose Bierce (not originally published as a book, BTW) and A Confederacy of Dunces, by some other guy.