InstantActionIA is the new thing from GarageGames. Install a little browser addon and it allows you to play some really nice 3D games. Marble Blast Ultra in a browser window? For free? Hooray! I guess the eventual plan is the base game is free, then you pay here and there for new maps and stuff.
Anyway, they put ZAP! up, which is awesome. ZAP! is a top down vector shooter. It will remind you of Geometry Wars. Unlike Geometry Wars, ZAP! is multiplayer focused. It has a bunch of game modes taken from Tribes: DM, CTF, Hunters, C&H, etc. You can play with a keyboard and mouse, but it supports gamepads which I highly recommend. Maybe we can get a game going sometime.
Its free, and I believe InstantAction itself is in open beta so anyone can sign up. Worth checking out.
