A perpetual topic of discussion in FOSS Communities.
Code is the real output of FOSS - When there is free software available, we can all contribute, evangelize, help people use it. That is why I strongly feel it is the primary aspect of running a community.
Building good software that people actually want, and find it accessible to use is the hardest thing engineers can do. Once we have that, the community then forms around it to improve it and take it to the world.