Donating money to organizations!?! Since the point of most moral behaviour appears to be to signal what a fine individual you are to your peers, donating to organizations seems like a terribly ineffective way to do that.

Perhaps consider doing a sponsored run - or something else that actively involves your social network - like plaguing your friends with cause invitations. Such actions are typically far more effective at signaling your good nature to your peers than attempting to do something that is actually helpful to others.