yoyo@home
They have applications for PPC and Intel macs, as well as windows and linux.
It is a math project, running OGR:
Golomb ruler - Wikipedia, the free encyclopedia
Edit: This project is basically the OGR-25 project from distributed.net, with a BOINC wrapper around it. So this would be a BOINC way of running it, instead of using the distributed.net client. The combined results are submitted to distributed.net as a single user under the yoyo@home name:
stats.distributed.net - OGR-25 Participant Summary for yoyo@home BOINC Wrapper
I believe that the project admin is working on having our own WU submitted under own IDs, so that we would each get individual credits. But for now, it is a group score.