Message from 2021
This post is pretty old! Opinions and technical information in it are almost certainly oudated. Commands and configurations will probably not work. Consider the age of the content before putting any of it into practice.
I used Prolog in a comparative languages course. The biggest program we did was a map-coloring one (color a map with only four colors so that no bordering items have the same color, given a mapping of things that border each other). I say biggest because we were given the most time with it. I started out like most people in my class trying to hack the language into letting me code a stinking algorithm to color a stinking map. Then I wrote a test function to check if the map was colored and, in a flash of prolog, realized that that was really all I needed to code.http://c2.com/cgi/wiki?PrologLanguage (via programmingisterrible)