BlackBerryCool » MySpace, eBay come to BlackBerry via mdog.com
Honestly, this is a MUST for anyone's bookmarks. You sign up for an account then pick and choose which websites you want bookmarked in your personalized portal (which you will bookmark in your browser). You can access MySpace, Facebook, eBay, etc. in a WAP-ish format (mobilized content).
I had some issues with the ability to login to MySpace, at first, but now it's working just fine. WOOT! They have a demo available from their homepage. www.mdog.com/pc/index.php
...the only drawback I see would be adding your peers' blogs in there, as it appears they'd be accessible by anyone in the world with your login name. I'm not quite sure how personal you'd want strangers to be with your friends, ya know?
Anyhow, here's a full list of the bookmarks (along with an idea of what this will look on your device: www.mdog.com/bookmarks.php