Firefox with Greasemonkey: If you find search results on popular search engines like Google, Bing and Yahoo Search to be a bit bland, Colorful Search will colour code and group your searches for easier identification.
Once you've installed Colorful Search, every time you perform a search at the supported services — Google, Bing and Yahoo — the search results will be colour coded. The colour coding occurs based on domain so you can easily see if the results for your search are coming from the same place. In the screenshot above — a portion of the Google search results for "Lifehacker" — you can see results from multiple domains are coloured differently.
Have a handy tool for enhancing search results? Let's hear about it in the comments. Colorful Search is a Greasemonkey script and works wherever Firefox does.