Where I live, the main university has a "University Surplus" store where things like that go to be sold dirt cheap to tech-savvy folks who already know it's not

Where I live, the main university has a "University Surplus" store where things like that go to be sold dirt cheap to tech-savvy folks who already know it's not garbage yet. $50 and a Linux install disc and you've generally got a fully working still fairly modern(ish) machine (modern enough to easily support some basic upgrades [GPU, RAM, HD, etc] if necessary for your intended purpose) all ready to rock-and-roll. Win/win for everyone involved. The University gets a bit of money out of it, anyone who wants or needs a cheap machine gets one, and the landfill gets to avoid some unnecessary e-waste.