Mozilla Google Hack
neat little browser hack for IE 5 for OS X.
Actually I've been using something very like this for Mozilla (all platforms) which consists of defining a bookmark for Google with this url:
http://www.google.com/search?q=%s
and then setting its keyword to "gg." Now you can just type "gg searchterm" into the location bar, hit Enter, and there you are. Extending this to highlighting browser text and then clicking a link to search for the highlighted term is left as an exercise for the reader.