I like Debian a lot and find great joy in keeping old computers around as workstations, proxy servers, file servers and the like. The proxy, for example, just got upgraded from a 486 with 20 MB of RAM to a Pentium Pro with amazing 128 MB of RAM. Linux is perfect for these purposes.
Most of my hardware was given away by friends or taken from junk containers. While I think that electronics freeganism is nice and reduces waste, the greatest benefit is that it's very educational.
Also: Electronics hacker since the age of 5. MSc in Electrical Engineering / Communications Techonogy. Hacking analog and power electronics for industrial robots as a job.