Use your screen saver to search for intelligence with SETI.
SETI@home is a screen saver program that uses home computers connected to the Internet in the search for extraterrestrial intelligence. This free program analyzes radio telescope data for the University of California, Berkley.
In order to analyze the digital mountains of data that comes in it would be necessary to spend billions of dollars on computers. Instead, UC Berkley came up with a better idea.
The UC Berkeley SETI team has discovered that there are already thousands of computers that might be available for use. Most of these computers sit around most of the time with toasters flying across their screens accomplishing absolutely nothing and wasting electricity to boot. This is where SETI@home (and you!) come into the picture. The SETI@home project hopes to convince you to allow us to borrow your computer when you aren't using it and to help us "…search out new life and new civilizations." We'll do this with a screen saver that can go get a chunk of data from us over the internet, analyze that data, and then report the results back to us. When you need your computer back, our screen saver instantly gets out of the way and only continues it's analysis when you are finished with your work.
This makes an excellent screen saver for libraries in all settings. It uses computer "downtime" more productively, and encourages scientific thought among patrons. Who knows what you will discover?