This is fantastic. ‘The Global Village Construction Set is a set of 50 tools/technologies for building post-scarcity, resilient communities.’

It's all the mechanical tools your hypothetical post-crash community would need, made in your garage. The tools (currently including a miniature tractor, a brick-maker, and a tracked hydraulic lifter) are built from a set of shared modular components, and appear to be relatively simple to assemble for anyone handy with a welder. Watch the video:

Global Village Construction Set from Open Source Ecology.