Some reasons why I love Opera 6.0 (at least over IE and Netscape, the only others I've used...):

1. It's free.
2. The tabs at the bottom turn blue when a page is done loading.
3. Any easily customizable hotlist.
4. Turning off the images to speed things up.
5. The transfer window that saves files I haven't finished downloading.
6. E-mail, messaging, and news, all built in!
7. One click closes ALL of the windows.
8. Mouse gestures.
9. It's got a cool icon.
10. AO's scrollbar isn't purple.
11. Search boxes on the main screen.
12. It's one word.
13. It's free.

Be sure to add reasons why you love/hate it.