I used to use the galeon web browser. I got used to having tabs on the right side of my browser; I can have lots of tabs and read what is in them. This works in part because I devote one workspace entirely to a full-screen browser.
When galeon maintenance ceased, I did not update until I found the vertigo Firefox extension. Then I stayed on Firefox 1.5.0.x until vertigo supported Firefox 2. Now, I have been staying on Firefox 2 because vertigo does not support Firefox 3. This is starting to feel familiar.
Today, I found a mention of Tree Style Tab as supported by Firefox 3. Trying it out, I was pleasantly surprised; the configuration options are better, and I like the tree style where you can see which tabs were opened from other tabs (this can be disabled if you don’t like that feature, though).