For the love of watercolor painting, a fantastic way to give back is to donate a small piece of art to a charity event. There are a number of events that put out a Call for Artists. Many are only looking for postcard sized art.
I donated a 4x6 postcard sized watercolor to the Twitter Art Exhibit and also Visual Aids. Both these deadlines have already passed. The Twitter Art Exhibit is on right now at the Moss Bibliotek in Norway and will be on display through January. The Visual Aids Post Cards from the Edge will take place in NYC in January 2011.
This is a great way to give to a charity in need. They collect the art, put it on display, hold a fabulous opening and sell it to raise money for their cause.