Lexisum is an ajax application that displays Wikipédia content as you type and make print-friendly copies of Wikipedia article summaries. It is really fast and very useful. You dont have to go to Wikipedia and search, you can just do that in Lexisum.

It is easy to use, just enter your search term and Lexisum will search Wikipedia while you type and return only Wikipedia summary, not the whole article. To read more, click on the “Read Full Article..” link at the bottom of the article summary. You can customize your article summary to A4, A4 Small, A5, A5 Small, A6, Black & White, Antique and Mix formats. You can also change the mode from visual to print mode.

Check out Lexisum at http://lexisum.com/. It is available in 9 languages and requires no registration.