This tidbit of a tip came up at mozKit today. The Mozilla browser and Firebird have this nifty function where you can select a piece of text and you can do a "Web Search for..." it in the context menu (right-click). Great time-saver for people who search often like me. Funny enough, I do recall myself wanting to always make use of that function when I noticed it quite a while back, but always forget and instinctively type into the Search bar on top. Must make sure to use it from now on.
Also, in the context menu there is a "View selection source" option that allows you to view the HTML source of your selected text/image/etc. - pretty nifty, pretty useful for web developers who want to check out their HTML source and not have to search through the entire clutter of code.