Very nice list, thanks to Peter for putting this together.
It's worth noting that for learning/basic experimentation there's lots of even cheaper chinesium stuff available on ebay:
https://www.ebay.com/sch/i.html?_from=R40&_nkw=FPGA+board&_s...
[edit]: For those who want to try, while back I bought a couple of low-end boards from an ebay vendor called qmtech and very happy with them.