DISCLAIMER: This might sound like a promo because I'm so in love with this program.
My favorite thing on the internet is StumbleUpon. It takes you to random web pages all over the www, you can make "friends" with similar interests and stumble to their favorite pages, and it logs which pages you liked so you can go back and log in to go back to those pages, so it sortof works like a bookmarking tool that you can access from any computer. I just love it. I'm "punchypinky" so make me your friend if you sign up.