It wouldn't take too much time to get the 68k AROS flavour going... There is a bounty for it, someone on the mailing list is preparing to take it on too!
There was quite of bit of talk about using an ST emualtor to run 68k Linux and then start by getting AROS hosted on that first (which should be really quite a straight forward process), and then get the OS running native from there!
Would be great to have a free 68k Amiga OS :-)