The question was basically: what are things liberals and libertarians can agree on.

Not exactly, though I probably gave that impression because that's the two sorts of people I get along best with. A conservative/libertarian coalition could be worthwhile, and I can dream that there might be projects that would pull in a really wide range of rationalists.

One thing that I should have brought up is that my point of view is very American. There may well be collaborations and projects which are more oriented towards other parts of the world.