It's almost a cliche in Western culture. For some reason, those swanky-looking leather-bound backgammon sets became either the mark of tasteful distinction or the default Christmas gift when you don't know what else to get. I see them in households everywhere. Unopened. Unplayed. Checkers still in the little sealed plastic baggies. Unloved. I don't know, I guess backgammon sets got advertised in the back pages of Playboy during the '70s or something; it has that kind of aura.
Anyway, backgammon is a geek's game all the way. It is so because winning it depends so much on knowing probability. There's a fantastic amount of jargon involved and about a dozen methods to analyze positions.
GNU Backgammon is fancy and feature-rich. You can customize from dozens of board designs and 3D or 2D layout. Choose from nine different skill levels, set protocols for the game like auto-play on obvious moves, get move hints and oodles of position analysis, and even set dice behavior - random, custom picks, or anywhere from "best possible" to "worst possible" rolls per turn. That last feature makes for a particularly hilarious game, and it's educational because you can pit computer-vs-computer and set one side for best rolls with worst skill level, the other for best skill level with worst rolls, and prove that skill still beats luck - in the long run, anyway.
A game demo
If you don't know the rules of backgammon, here's a great educational site about the game.
By the way, I should mention that the aforementioned Backgammon Galore site also has an article on GNU Backgammon, with a very positive review and an extensive manual going into the mind-boggling complex game mechanics and analysis features.
For those of you who know some of the rules of backgammon but don't get what all the fuss is about, let me demonstrate how much drama and suspense there is in a game that is the perfect blend of skill and luck...
1. Observe this position. I'm green. You'd re-double here too, wouldn't you?
2. But here is my next roll. The realization that there was no way to play this roll without leaving an open blot wiped the cocky grin right off my face.
3. I figured it was logical to play and hit from the six-point. That way, the only roll that can ruin my life is a four; GNU BG got a 2-1, blocked. I, too, rolled a 2-1, and hurriedly rescued my open blot. I thought I was saved!
4. A few moves later, and now the board looks like this. I'd never intended for the opponent blots to hang around so long. But look out, I threw another Bozo roll. Once again, there's no way to play it without hitting again and leaving a blot open again!
5. A couple moves later, and this position is showing weaknesses I'd never anticipated. I got the four I was praying for to cover my four-point, but with a three along with it which dooms me to leave a blot exposed for the third time in a row!
6. So here we are. Once again, four is the roll of death for me.
7. Got it. Twice!
8. So that means not only can it chomp my blot on the four-point, but have my blot on the eight-point for dessert. Then, since it has two more fours to play, it can also snap a checker from its six-point to the two-point, making a pseudo-prime with two of my checkers on the bar!
9. Here's the game a few moves later. I'm completely blocked, no hope of recovery from here.
That's just an example of how your fate can change in this game just like that. Just sharing my blunder with you; I know some of you backgammon-geeks out there are already chuckling at my whopper.