I'd like to add on the following non-beta/alpha BOINC projects.
Rosetta@Home
Rosetta@Home is becoming one of the most popular medical distributed computing projects available for the BOINC platform. It has a highly active community and project team who are constantly giving updates on the project's progress. Rosetta@Home helps to determine the 3-dimensional shapes of proteins in research that may ultimately lead to finding cures for some major human diseases such as HIV, Malaria, Cancer, and Alzheimer's. This is a non-profitable project.
Einstein@Home
Einstein@Home is a very popular project that helps to search for spinning pulsars in space using data from the LIGO and GEO gravitational wave detectors. Unknown if this is or isn't a profitable project.
World Community Grid
World Community Grid's mission is to create the largest public computing grid benefiting humanity. Currently their most active project is the FightAIDS@Home project, which helps to find a better vaccine/cure for the HIV/AIDS virus. This is a non-profitable project.