The ability to discover new material based on the clusters that results from a Carrot2 search has been a huge help. Nothing else quite like it-- try their desktop app, too!
Great! but the extension cannot be installed with Firefox for ubuntu (14.04).
I signed up for an account just to review Carrot2. This is the greatest search engine ever. It actually makes the internet useful. I cannot believe the garbage that the big search engines pull up. Carrot fetches relevant and diverse information. You will not believe the difference. Enjoy!!