I had access to either an Alto or a Dorado during my co-op terms at Environment Canada (the weather service) back in the late 80s. I had a keen interest in OO at the time, but I can't remember this machine having a Smalltalk. Whenever I was able to access it, I spent time amusing myself hacking LOOPS (pre-cursor to CLOS - OO Lisp).

I also had access to a Mac, had an HP-9000 unix workstation (running X Windows) sitting on/under my desk, and had some exposure to Smalltalk-80 at the time. What blew me away was how mature and strange the Alto was; it was so obviously advanced, but was so difficult to understand. At that time, it was an 'old' machine, but somehow seemed like it was sent from the future.