This extension adds favicons -- those little icons you see in your address bar when you visit a page -- to Google's search results so you can more easily see what site each link is coming from.
Not only does this spice up your bland search results a little bit, but it makes it a lot easier to sift through the stuff you don't want, and find the stuff you do. I've found it's particularly useful when I'm searching for specific problems -- I can easily tell which links are from a forum and which are blog posts that probably aren't closely related to my problem. There aren't any settings you have to fiddle with, either -- just install it and enjoy your new search results page.
Faviconize Google is a free extension for Chrome and a user script for Firefox with Greasemonkey installed (the user script version doesn't seem to work on Chrome).
Faviconize Google for Firefox [Userscripts.org]