More cool stuff here:

http://opensourceecology.org/wiki

Note, it is not exactly "free" when you have materials costs on everything, but people pitching in on tools and a location to build out in the middle of nowhere in places where real estate is dirt cheap anyway means you can leverage smaller amounts of individual person's cash into a better overall lifestyle but it is only going to work when people pitch in and work as a team while respecting individual resources and effort. Otherwise, you have someone with money having to pay the others to do the work and that's where there is no guarantee of cost effectiveness on open source maker stuff since there is no way to predict its value in comparison to the outside open economy where say, superior design equipment might be available on the farm auction market, or your economic profile allows for bank financing of big ticket items which will enhance production at faster rates or lower overall production costs.