> One thing I was thinking about that would be really interesting

> would be a talk about Lisp Machines,

 

You're in the right town for that.  But Lisp Machines are a big topic area.  That's kind of like a talk on "the C language and things it has been used for".  And the communities started off the same and then diverged into different cultures such that everyone's reality was not even the same.  But even glossing that, there are issues of operating system, editing environment file system, editing tools, mail reading, patching tools, marketplace, etc.