Yes, you may have Tumblr, but when you get to that point on your dash when you feel like you’ve seen the same posts before, here’s some free, and probably nice sites to visit.
http://care2.com/clicktodonate (and some of the links there)
http://thehungersite.com (and some of the links there)
http://clicktogive.com (yeah, links)
http://www.worldlegacy.org/ (two links)
and you can go to http://thenonprofits.com in case I forgot any.
…so…how about it?