Second Life 

As a non-profit, the computers we have to work with aren't exactly the latest and greatest. But about once a year, we get a grant and can replace a few (about 5, or 10% of our pool) desktops with new (well, newer) ones. After I set up those up for the users, the old ones come back to my office. Or sometimes we'll get donations of PCs which are too old for even us to use. Since I dislike throwing things out, part of my job is to find new homes for these dinosaurs. I'll (securely) wipe the hard drives, and if it's a donation, add RAM where possible. Then I list the specs and post them on Craig's List for about $15 to $40 each. These aren't blazing fast , but they'll still connect to the Internet and can do homework. If one of our clinicians knows a family which could use one for their kid, I'll add a keyboard and mouse, and take the time to set up Windows XP, Microsoft Security Essentials, and Libre Office and pass them on for free. Better than sitting in a landfill!