Very Useful and Fun, too. Rated 5 out of 5 stars

It is phenomenal! I was looking for some software and it came up with no less than 266 sites that I'd never heard of to try. And because the software was obscure I was able to find it. I also love that you can take the results of a match and keep each in a folder. It makes it very easy to add to your bookmarks when you are finished browsing. This add-on makes surfing the web fun again for me, because I was in a rut going to same 20 or so sites everyday. Stumble Upon is good for discovering sites, but it is more random, and one at a time. Similar Pages gives you hundreds of sites on something you are interested in at the moment. Thanks for making this add-on! I am having a lot of fun with it.

This review is for a previous version of the add-on (1.0b1.2010100710).