Just wanted to add for the record / archive: Someone here had suggested http://www.scn.org/scna/pcdonate.html The site seems a little dead so I emailed them them last week. They didn't respond to my email until this week. So, they missed the boat this time, but they say they're still accepting computer donations. I don't know the details, but I'll consider them as an option worth investigating next time I have donations.
-- Francois Caen