I have been doing local voluntary work that I discovered through that site for the last four or five years. (I don't want to say what I was doing as it is a sensitive subject).
It has been a very rewarding experience and I made one very good friend who has enriched my life enormously. However the management changed a year ago and I resigned at the end of last year as it seemed that my personal safety was the least important consideration. Some of these do-gooders can get a bit carried away by the cause. It seems that just as everyone is jumping on the bandwagon I am jumping off.
There are plenty of other voluntary work opportunites - for example I have helped publicise English Touring Opera