I'm poaching other stuff here, as a kind of blog note to myself. To open an multiple shells in emacs, without installing any extra code, you do this:
[C-u] [M-x] shell, and give the buffer a name at the prompt
I got this from this emacs tutorial, but was lead there by comment on this blog post. Between the post and comments there are a number of pointers to useful techniques and code for working with multiple shells in emacs.