Researching the sam editor is strangely intriguing. See Rob Pike's description of the command language: http://doc.cat-v.org/bell_labs/sam_lang_tutorial/sam_tut.pdf
plan9port http://swtch.com/plan9port or
and try to get sam running on top of your linux box.
But cool, nevertheless.
I am a bit ashamed the coolest operating systems on the market today are either Unix-derived/inspired or a lame rehash of VMS.
There is something wrong with this.
OTOH, Lisp is still going strong and regaining lots of followers. Maybe the folks at Bell Labs accidentally hit a local maximum in the OS space...
But I still think we should understand what really happened.