My N900 runs MVS 21.8 with the help of the s390 Hercules emulator. It's amusing to watch it IPL and run TSO sessions with about the same response time as a circa-1980 IBM mainframe. It's a data center in a handheld, 30 years out of time.
What's it good for? Spending a nostalgic evening, killing a beer or two... and that's about it. I imagine the same thing goes for that Windows 3.11 hack.
This is awesome cool! After seeing the website made to look like 3.1 on here a while ago, I have been looking for some old install media to give it a spin.
http://www.dosbox.com/