Boounce is a simple browser add-on available for Mozilla Firefox and Google Chrome that helps you bounce between search engines, topical databases, and searchable websites. It mercifully eliminates duplicate results from Google, Bing, and Blekko.
This works quite well if you need to search through a lot of sites quickly. However, you should only use uncomplicated search terms containing words that are not likely to be filtered-out of the results by the default porn filters of the sites you are searching.
If you copy a lot of material while searching, then in the addon’s options deselect “Use text selection as search term”. This is particularly annoying if you cut and paste to MS OneNote as you conduct your research.
One feature I really like is the ability to right-click on webpage search box to add it to the list of boounceable sites.
The list of search sites included with Boounce may be found at http://www.boounce.com/search-engine-list/