Rated 5 out of 5 stars

I can’t tell you how much time I’ve lost jumping from one website to another for hours and hours, still not finding what I’m looking for. Doing my web searches using the clusters add-on for Firefox has been a huge help. In any given cluster I’m sure to find something relevant because someone else has already done the legwork. And I use them myself to organize my information and pay it forward to someone else. A fantastic research aid!