Lenovo Thinkcentre Tiny on eBay. The M600 model is about the slowest / cheapest available and you're looking at $60ish, often with an SSD. Unless you need the

Lenovo Thinkcentre Tiny on eBay. The M600 model is about the slowest / cheapest available and you're looking at $60ish, often with an SSD. Unless you need the GPIO or have a pi-specific purpose, used thin clients or tiny PCs make more sense for a home server now IMO.