BuddyPress.org

+1 for donating monies to your favorite add-on plugin devs, or supporting their business models. BP is awesome, but without community developing all these add-ons, it would be half as far.

Some people have tried to do a Donate Friday. So, this Friday pick a plugin you use often and donate five bucks to the dev. take the ten minutes to poke aroudn their site and look for a donate link. If all else fails, find their email and paypal money to that.