My thoughts on further social business opportunities: how about rationality consulting? If SI/LessWrong can establish enough credibility as rationalists this is worth money to both non-profit organizations and for-profit businesses, as well as potentially to consumers (as with Eliezer's rationality books). Rationality consulting would probably have to be done for free at first, of course. As a secondary benefit, this would also help with the ongoing effort to measure the impact rationality training has on an individual or an organization.

On a meta level, offering a prize may be a good way generate social business ideas, since the prize would more than pay for itself if the idea is profitable enough. Resource strategy consultants for non-profit organizations do exist, and business entrepreneurs (having expertise in resource strategies from another angle) might also like the idea of a prize.

This is also a topic that SI's Volunteering program can address, which I notice in the Strategic Plan that SI plans on growing.

Luke responded that "actually, a rationality teaching/consulting business is already in the works! That's the 'Rationality Org' we plan on spinning off from Singularity Institute."