I think running Linux on MorphOS, via some kind of box, like the one Mac on Linux provides (without actually running Mac OS X, which is illegal) would be a lovely idea.
There is also another one, dear to my heart. ARANym, which is a very strange acronym, but stands for Atari Running on Any Machine. It is a full 68K including FPU and MMU!
It allows you to run Atari software...including a completely legal clean box TOS called FreeTOS, but the idea here, is that with that MMU support, you might also be able to run Linux m/68K and/or FreeBSD.
ya ya sure sure, so what...not the most sought after OS's in the world...but it would be a fun geeky thing, if no other emulator was available, you could still get a linux live of sorts on your machine.
Apples old A/UX actually does run inside of Fusion on a real amiga, ....wild, wacky stuff.
I was originally working on porting linux m/68k to some kind of virtual machine, but now I simply think its a good idea, but won't work on it. I'm thinking of getting AROS, and maybe poking around a bit, but it doesn't seem to be finished yet.