http://www.flownet.com/gat/jpl-lisp.html
Interesting story about how Lisp was used at the NASA JPL.
It also shows that Lisp can be fast. It's actually not surprising, most things invented the last century are fast but their current implementations are usually slow.
It's possible to run Lisp on surprisingly small processors. My first Lisp was P-Lisp, which ran on an Apple II with 48k of RAM. The three-disk towers-of-hanoi problem was about at the limits of its capabilities.