#Retina ZIII
At one point the system part of the release only was here. However, you can
order it, either for free or for I think $25, depending on what version you
have and from whom you bought it, from NoahJi's, and you'll get several
programs, like xiPaint, as well.
It supports OS3.1 well enough – I can vouch for that, since I have 3.1. 😉
Mr. Zombie