I have a book called "The Art and Craft of Problem Solving" which uses climbing terms to describe various techniques and tools used in IMO problems. It wasn't a very forced analogy at all.

Also, for interest's sake, a few years ago a physicist (http://insectnation.org/projects/nightclimbing/) even scanned in an old book on climbing; t'was pretty nifty! (but slightly off topic here probably).