Altitude, anyone play this?
 

(I took this straight from the site, I admit. This game really is a fun and enjoyable independent MMO-esque type of game.)

Altitude is a fun, original multiplayer game with a bunch of cool unlocks and game modes. It's easy to learn and perfect for quick 10 minute sessions when you're busy, or way longer if you're bored. Very fun multiplayer action. Make sure to try ball mode once you've learned the basics.

Free 3 hour demo: Windows, Mac, Linux, Steam
(If you use the above links you'll automatically friend me in-game, if you hate me just paste altitudegame.com into your browser)

Screenshots: 01 02 03 04 05

This game is a ton of fun to play, small download, runs on just about any system, Windows/Mac users can play on the same servers, perfect for quick 10-20 minute spurts if you're busy, and basically everyone needs to play it. Just download the free demo already, you'll be glad you did.

More info including trailer: altitudegame.com