I do plan to start talking about my tithing, slowly, as it comes up in conversation. If everybody who decided to give rationally influenced at least one other person to do so too, the idea grows virally. But, gently, gently. Nobody's convinced by brow-beating moralising.

In academia, especially, forming a group that thinks through the impacts of different charities (and that potentially helps you decide where to donate) might allow you to get others engaged in a manner that feels more like recognizing their status/brains, and asking for intellectual help they might like to give, than like moralizing.