if i recall correctly i think the processor could multi-task. i think it was sinclair Ql that linus torvalds started his low level programming on, could be wrong as it's been a long time since i read the book on the birth of linux and opensource, should read this book if you get a chance.
http://www.amazon.com/Rebel-Code-Lin.../dp/0738203335

i think some of the emulators are being ported to the n9, i'm lookin forward to the c64 one. brings back memories.