Some years back, I bought a copy of New Rules for Classic Games, by R. Wayne Schmittberger. (I probably don't have to tell you it's a great book, because you're already imagining the horrors that poor soul had to endure from their schoolmates based on that unfortunate surname. If you can live through such a thing, that's natural selection at work - we're looking at a superior lifeform now.)
Now, if you're like me, you've probably thought to yourself "Chess is kind of rigid. Why can't I mount surface-to-air missiles on the bishops and wire the king up with enough explosives to take out the whole board if anyone's foolish enough to put him in check?" If so, you'd appreciate this book. I don't think it covers that specific example, but it does offer up a wealth of variations to breathe new life into the games you already own.
(Although, actually.. Knightmare Chess isn't too far off from what I just described)
Now, you have to understand I used to collect Pen & Paper Role Playing Games and all their expansions, knowing fully well I would never have a chance to play them. I just enjoyed reading the rules and imagining possibilities. So it wasn't too frustrating that I could never find anyone to try out the stuff in this book. But I won't pretend it didn't bug me.
Still, I always thought it would be great to buy the rights to this book, and put out a CD with hundreds of innovative but familliar games to play. That would give you computer opponents, it would open the search for players up to the internet, and having it on the computer would keep track of all those pesky variables. But I didn't think anyone would actually buy the thing, so that's as far as the idea ever went.
But, check this out. I'm searching the web for a replacement chessboard, and what do I come across? Zillions of Games. Which is pretty much exactly what I've been dreaming of.
Poke around their site to get an idea what all they offer. It's pretty amazing. The CD comes with 321 games, and there's roughly 600 downloadable to add on for free. And they're cool games. I know my brother was looking for computer versions of Mancala and Abalone. I'm more interested in the new variations - games like Quantum Chess and Magnetic Chess call out to me.
What's more interesting, though, is that it comes with tools to make your own games. Once you've defined the rules, the computer can play against you with simple brute-force A.I. or you can post your game for the world to share, and seek out opponents online.
So, yeah. A piece of entertainment software which fosters creativity by helping you build games which further encourage abstract thought... You don't get a lot of that these days.