Imagine making a small charity donation for free every time you search the web with a search engine - well now you can. The search engines make money from different kinds of advertising on their site. To make more money the search engines try to get more people to do searches with their engine. Therefore many search engines are willing to take a portion of their revenue and give it to sites which host their search box and give them "searches".
Now suppose there was a site that had an affiliate agreement with one or more search engines and would donate all or part of the money they get when you make a search through their site. As you probably guessed, there are such sites.
Its totally free and every search you make will donate money to your favorite charity. You have nothing to lose.