Use Firefox smart keywords to make it easier to use your favorite search engines to find what you need faster.  Takes about a minute to add a web site to your Smart Keywords list, and then you have an easy way to search websites right from the browser Location bar (where you usually have to type the whole web address).

Say you visit wikipedia all the time to look up things. You go to wikiepdia.org and click in the search box and enter whatever you're searching for, and click Search. Lots of clicking, lots of steps.  If you add wikiepedia to your Smart Keywords, you will be configure it to do something as simple as type "w pirates" to search wikipeidia for this topic

Here's how to set it up: http://www.mozilla.org/products/firefox/smart-keywords.html

Note: this is not an extension to Firefox. It's all right there. The Opera browser has had this feature for  a long time; here's how to use it in Firefox.