I may be a little late to the party, but in the last 3 months I’ve begun using this feature more and more:
Typing something in the address bar does an I’m Feeling Lucky search on Google.
Sounds simple, and perhaps not that useful all the time. I was worried I’d get taken to wildly inaccurate sites. Happily if the top match isn’t as close as you’d like (as defined by some secret sauce which does a great job I must say), you get taken to the Google search results instead.
I started using this feature more when I switched to Firefox 3 (thanks pesky 100% CPU and memory leaks!) and the Google Toolbar broke. By default I map my search bar to Wikipedia given how often I use it. Now I find it completely indispensable, and I’m at a loss when using other browsers…
The main benefit is I don’t use bookmarks at all anymore. For example, I can just type “hacker news” and get taken to http://news.ycombinator.com/. I can type in “download firefox 3” and I get taken to the download page for Firefox 3. I can only imagine this is a huge boon for those using voice recognition. There are some other nice side effects. Try typing a site name and a concept on that site, eg “wikipedia triops” and you don’t need to set up smart bookmarks either. Although it’s rare for people to use the Google toolbar and a different search, it is handy now having a shortcut key to search (ctrl-L).