This post is dedicated especially to Roytam1 (I saw his hardware collection on his old website).
https://www.parkytowers.me.uk/thin/hware/hardware.shtml
Which thin clients (terminals) I currently have (in brackets drivers available, Linux - always):
HP: t430 (W10), t520, t620 (W7+)
Dell: Wyse 3030 (very energy efficient, W7)
Interesting:
HP t630 2GHz (x4) max 32GB RAM but power consumption is higher: 28W (pros: use RAMDisk if you are using apps which consumes a lot of RAM).
Not interesting:
Any terminals with Atom CPUs - they are just very fast calculators.
Notice:
You need at least 16 GB flash disk shipped with thin pc to install W7 (my all have 32 GB).
Prices: aroud 20-60 $.