Ask HN: What to do with two old desktop machines?

Hey HN,

I have two desktop computers with 2-year-old quad cores and 8gb of ram. They are still somewhat powerful machines, but they sit in my closet because my MacBook has all of my needs completely covered.

I thought about donating them to a hacker house, like noisebridge - but I hear that they'd probably end up in pieces and never really used.

What should I do with these machines? Happy to donate processing power (put them online in my apartment), but I'd rather just physically give them to a good cause.

Cookie points for crafty ideas.

Thx HN & merry xmas :)