Ever wanted to play an MMO where you are not a druid, or an elf, or a mage, but a TANK? Then World of Tanks is for you.
The game, by Wargaming, lets you drive pretty much every significant tank of the mid-20th century, as you join a team of tanks to go off and fight another team of tanks. Like Team Fortress 2, or Counter-Strike, only, with tanks.
Your armoured vehicle of choice is your "character", which you level up as you play, while the game also has some peripheral elements like strategy. It's a unique beast of an MMO, then, combining real-time, squad-based combat with more persistent genre elements like character progression.
A second round of open beta testing is about to begin, which you can sign up for here.
Having not gotten around to it last time, I've made sure to sign up for this round. Sure, I normally can't abide MMOs, but then most MMOs aren't called WORLD OF TANKS.