One of the most unique "interactive fiction" titles you'll ever play, Andrew "Zarf" Plotkin's Lists and Lists is a great example of what modern text adventure interpreters can do.Instead of coding another IF masterpiece that he's famous for, Zarf instead delivered Lists and Lists-- an excellent tutorial to the real-life Scheme programming language (a dialect of Lisp). Sure, there is a plot of sorts, but it's a thinly veiled excuse to deliver programming lessons. Basically, your alter ego in the game is there to learn Scheme, and the lessons are doled out by a good-natured genie who gives you lesson goals and advice. The in-game book describes basic Scheme syntax and general programming tips in excellent, user-friendly manner, and before long, you will find yourself able to program some basic algorithms in Scheme. Lessons progress in a logical manner, and you can go at your leisure. Not all of Scheme's syntax is represented, but it's still a great "game" that is very educational. If you're a non-programmer who's interested in how programming works, Lists and Lists is the perfect introduction. I was tempted to put this in the "Education" section, except that I know how few people venture there ;) Two thumbs up!