in my own surfing the net today, i discovered good old www.habitat.org again. a great organization, and a travel planner to boot. They have new opportunities on that website to join a crew to build homes or rebuild communities, and, for those of you who were thinking of exotic travel .... they have a program in Papua New Guinea, and two in New Zealand coming up ... PNG sound grand, and truthfully, you can only visit PNG safely with some organized adventure crew. the two in NZ are in great places. one on South island, with opportunity to visit Stewart Island, a bird watchers delight. and the north island, near Auckland, which is a grand part of NZ.
Connect / link an LL vacation with something good for far off neighbours... and what could be more 'far off' than PNG.
something closer to your current location may also be on that website