The Lenovo X220 are great little machines from 2011 that still have plenty of life left in them. I picked up mine on Ebay for AUD $200 - 4GB of RAM, i5 CPU and 120 GB Samsung SSD. Excellent Linux support at a very reasonable price. I use one at work instead of the provided Macbook/Dell options, and it’s great.

It’s also upgradable - the battery, SSD and RAM are all easily accessed. The only shortcoming is the screen resolution at 1366x768. I use it as a portable desktop replacement, so it mostly lives in a dock ($25 on ebay), so the resolution is not a problem for me.

I spent some of the weekend getting it running with Coreboot instead of the stock BIOS.