[pjmlp]

Not only Acorn/RISC OS, but all 8 and 16 bit home systems.

The main issue is of course portability, but I had lots of fun with Assembly during that timeframe.

Do you know how RISC OS fares in the Raspberry PI?

[JamesAn]

I haven't used it yet, but it seems to be faring okay.

http://riscpi.co.uk/sales-riscospi/?doing_wp_cron=1403977657...

You can also download RiscPC or Archimedes emulators, e.g.

http://www.marutan.net/rpcemu/