The groups aren't always easy to track, but one barter club founder told Reuters her group was adding 50 to 60 new members every day.

While it would be ideal if these groups weren't necessary, they provide an important lifeline for poorer residents who'd otherwise have more trouble bartering goods. They also show how important social networking has become -- it's now the first place some people go for help in a rough economy, rather than turning to neighbors or the government. It also suggests that, as much as social sites have done to support communities in need, there's still room for additional help.