LibraryThing.com – A great place for book lovers. Catalog you library, discuss books, network with other bibliophiles.
Gutenberg.org – I’m sure most people know about this one already, but if you don’t, this is the place to find free public domain e-books. The have a great catalog.
Librivox.org – Similar to Project Gutenberg but for audio books. You can even volunteer to read for some if you’re so inclined.
Garyc.mooo.com:3232/sketch – This one’s just kind of fun. Draw a sketch and swap it with another user from somewhere in the world.
freealbums.blogsome.com – This is a blog that posts links to free, legal music. All links are for full albums.
CigarMonster.com – This one is probably only going to be interesting to people who enjoy a good cigar. They only sell one box of cigars a day, but the deals are great. Think Woot for cigars.