@tomxcd Linux: about 2001 on the Deloitte attack laptops (pen testing). Fedora. Later (2006 maybe) ubuntu as it was the first to support the free vmware server that wasn't RH or Suse iirc.

FreeBSD: since it was 386BSD in the early 90's, installed from 40 x 1.44mb floppy disks. Still prefer it over linux tbh.