I got an 800mhz G4 powerMac for free from work that someone was going to throw out!.
I currently have the MorphOS 2.7 demo on it. I'm still contemplating registering it. Not sure yet.
Free -vs- $1000+ for a hobby OS was a no brainer for me.
What does MOS license cost? AOS is like a 149.00 USD last I looked.