Hiya,
I used to play this game infantry a couple years ago, but lost track of it. It's a 2D multiplayer game played from an overhead view. It's not the greatest in graphics compared to what's out right now, but it has a pretty huge depth of gameplay with multiple classes, buildable/driveable vehicles, RPG elements in upgrades gained by experience, and so on.
Some kind independent soul has picked it up and hosting a server (much like what happened to Virgin's subspace, if anyone remembers that game). You can check it out here:
http://skills.googlepages.com/. The download is pretty small overall, since it's such an old prog.
I recommend checking it out if you're in for an oldskool thrill, it's a pretty great old game. Let people know you're new to the game when you come in and they'll help get you set up.
-Yojo