[personlurking]

It's certainly a great idea and would be excellent for getting a leg up on opportunities near where you happen to be living at the moment. The difficulty in it is the chicken and egg dilemma and the initial non-concentrated userbase.

I only know of various expat community forums and sites which anyone can find with a Google search and a few subreddits (like /IWantOut).

Edit: I found this via Google http://www.digitalnomadcommunity.net/