1 - www.piperka.net - keeps track of webcomic updates, and where I am at in archives
2 - www.stackoverflow.com - coding problems often lead me there
3 - It's a tossup. I usually don't spend a lot of time on the net aside from webcomics and looking things up. For third it is pretty evenly split between the Escapist, thecoolhunter.net, Amazon and www.imdb.com.