I picked up a thin client from Goodwill for $15. New enough to have USB & run Windows XP, old enough to have hardware serial/parallel ports, no WiFi, so easy to airgap. I have it running all my programmers: Data I/O 29B, GQ-4x4, and Bung flash linker. I couldn't get the Bung to work with ECP/EPP mode, so it's maybe a bit slower than it could be, but it works fine other than that.