The Amiga port isn't live. It hasn't been maintained for a while IIRC.
There are two important points that shouldn't be forgotten about aggressively pushing cross-platform: it retains developers and exposes bugs. There's a great deal of usefulness behind it, beyond simply making it obvious that the workstations we get today are shit.
I know OpenBSD's reputation is primarily security, but I use it for a different reason. It's simple, stable, and doesn't break.
Back when I was in high school and I had a lot of free time and all that, the various incarnations of Linux were a delight. Even after that, I still went with it out of inertia and spent many evenings tweaking Gentoo.
I eventually just goddamn gave up. I got sick of every upgrade breaking something in my system and then especially got sick of deciding between figuring out how to use wpa_supplicant and installing NetworkManager which screws up my network settings as soon as I plug in the Ethernet cable while I'm still on my wireless. In a flight of rage I thought ok, I've had enough of this crap, and went the OpenBSD route.
Seriously, it has all the nice parts of Plan 9 while still actually being able to run all the tools I need. I still have Linux and Windows boxes for the odd tools that don't work on anything else (I do embedded systems for a living, and there's a lot of vendor lockdown there), but for my day-to-day workstation, I found nothing better.