From Unofficial BOINC Wiki
 About the Arecibo Radio Telescope
The Arecibo Observatory is a very sensitive radio telescope located approximately 9 miles (14 km) south-southwest from the city of Arecibo in Puerto Rico. It is operated by Cornell University under cooperative agreement with the National Science Foundation. The observatory works as the National Astronomy and Ionosphere Center (NAIC) although both names are officially used to refer to it. NAIC more properly refers to the organization that runs both the observatory and associated offices at Cornell University.
The observatory's 305 m radio telescope is the largest single-aperture telescope (cf. multiple aperture telescope) ever constructed. It carries out three major areas of research: radio astronomy, aeronomy (using both the 305 m telescope and the observatory's lidar facility), and radar astronomy observations of solar system objects. Usage of the telescope is gained by submitting proposals to the observatory, which are evaluated by an independent board of referees.
The telescope is visually distinctive and has been used in the filming of notable motion picture and television productions: as the villain's antenna in the James Bond movie GoldenEye, as itself in the film Contact and in The X-Files episode "Little Green Men". The telescope received additional international recognition in 1999 when it began to collect data for the SETI@home project.
 About AstroPulse
One of the first applications to make use of the new BOINC Client Software is a Project called AstroPulse. This Project will re-examine the existing SETI@Home data tapes for a new type of signal, radio pulses that only last for a microsecond.
This type of signal is different from those which would be caught by SETI@Home. Since the pulses are so fast, they are Broadband Signals. We need the full 2.5 MHz bandwidth for maximum sensitivity, whereas SETI@Home breaks up this frequency band into 256 10 kHz sub-bands. Also, pulses traveling through the interstellar medium (the thin gas which fills the space between stars in our galaxy) become "dispersed", or stretched out in time. We can correct for this effect with a specialized algorithm (known as "coherent de-dispersion"), but it is very computation intensive, which is why this is a good Distributed Computing Project.
There are several possible sources for this type of signal. One possible source which is already known is called a Pulsar. This is a rapidly spinning neutron star which "beams" radiation at us every time it rotates. Our search may uncover new pulsars, since no one has looked for pulses this fast before. Another possibility is extraterrestrial civilizations - a series of pulses could be an easily recognized signal, and a pulse with negative dispersion would stand out as obviously artificial (natural dispersion always causes faster frequencies to arrive first). A third possibility is an evaporating black hole. It has been theorized that a black hole which completely evaporates will give out a short radio pulse at the end of its life, but no one has seen this happen yet. Our search will be at least 100 times more sensitive than previous efforts.