Zatikon

Zatikon is from Chronic Logic, who have produced a whole slew of interesting games over the years, including Gish and Bridge Construction Set. It's a bit of a departure from them, both for its business model and for its gameplay.

Gameplay first: Zatikon is a Chess-like turn-based strategy boardgame -- that is, not literally a boardgame, since it's played digitally, but very much with the feel of a boardgame. Each player has a castle at opposite sides of a 12x12 square grid board, and winning means occupying the opponent's castle. You have available some number of units of different types, which you deploy around your castle, then move toward the opponent. Different unit types have, naturally, different movement and attack capabilities.

So far, so familiar, but here's where it starts to get interesting: the universe of the game contains a huge number of different unit types, and many of them have special rules, "exceptions" in the Magic: The Gathering or Cosmic Encounter sense. You can click on enemy units to see what they do, and you're quite likely to be surprised with new capabilites in play. And naturally, such variable unit capabilities lead to a wide diversity of different strategies -- e.g., if you have a unit that can freeze another player's units in place, that drastically change the nature of the game.

As in Magic, you design your own army, that is, the pool of units you are able to deploy when you play. You try to imagine strategies centered on the combined-arms capabilities of different unit types -- and then may find your carefully refined ideas thrown for a loop when an opponent shows up with abilities that screw up your plans.

As for business model: unlike most of Chronic Logic's games, Zatikon is free to play -- to a point. Some unit types are unlocked only if you buy the game, but you can certainly play for many hours before getting the itch to plunk down your money. A "freemium" model, in other words.

It's got both soloplay and online multiplayer, and at least when I've been on, there have always been enough people around that you can actually find opponents -- not always a given for indie multiplayer games.

I'll be interested to see how Zatikon does; short-term, small-scale multiplayer games have never done particularly well on the Net, but the fact that it's free(ish), and that the game itself is genuinely novel and strategically deep, give at least a shot.