Comment by chiph

You can get IBM i (OS/400) running at home, but the hurdles are many. You need to have one of a specific set of PowerPC servers and need to "acquire" an operating system image. Which will be running in unlicensed demo mode. This YouTuber did it.

https://www.youtube.com/watch?v=mUwJk81YatA

It's long been said that the biggest obstacle to wider adoption of the AS/400 is IBM itself. They offer classes, but don't make it easy - you have to join COMMON (their user group) and/or be enrolled in a university.

https://www.ibm.com/university/power/ibmi/