Yeah OpenBSD is a decent OS, and a good desktop OS especially in todays highly hackable world - I just prefer FreeBSD for the general use and OpenBSD for firewalls, servers etc. The Linux kernel is alright, if a of a questionable design and architecture, but GNU, the userland stuff is outright horrible and is the main reason I won't touch GNU/Linux with a 39 1/2 foot pole. The GNU project and the FSF are convinced that proprietary software is the capitalism of computing and that it should all be socialised under a licence that forces you to keep it socialised.
I'm really interested in MorphOS and I used it on my PowerMac G4 as a demo OS, but I never really had any use for it beyond screwing around.
As far as IRIX goes I'd like to convince SGI to open it up under the MIT licence since they have stopped supporting it - if you have any ideas please PM me
.
I definitely agree the the Linux kernel is pretty poorly designed.
At least recent revisions can dynamically load and unload drivers.
As to IRIX, the biggest stumbling block to getting SGI to open it up is the competition it might provide for more recent SGI offerings.
Let's face it, that is what killed Open Solaris.