I've managed to get Einstein@Home BRP app compiled and running on the Raspberry Pi. It was a bit of a nightmare trying to compile as the build script that comes with the source over at http://albert.phys.uwm.edu/license.php was just way to automated for my liking. I had to hack and slash to get it compiled. I've had a look at the grav. wave search software and that seems even worse!
Need to wait for task to finish (for validation), but the application binary is available over on my project page if you want to give it a shot.