For those interested in learning more about what DAFS is and what's been
done with it so far, here are the links I've found
http://www.dafscollaborative.org
http://www.eecs.harvard.edu/~vino/fs-perf/dafs/
http://www.cs.duke.edu/ari/dafs/
It appears there's been work to build in DAFS support for both Linux and
BSD, but there's not a lot of data on how far that support has gotten.
Basically, it looks like a SAN type of protocol.