If you've had an eye on your Twitter stream, you've probably noticed the conversion over the last couple of months of a number of your friends' avatars from photos to 8-bit style graphics. That's thanks to Eightbit.me which moves out of private beta and opens its doors to the public today.

Eightbit.me lets you recreate yourself as an avatar in a throwback to the classic 8-bit video games. You can customize your hair, clothing, and glasses, and the founders promise more accessories and dressing options to come in the future.

But it's not simply a way to create funky avatars. That would get old fast. Timed (as most things are this week) to coincide with SXSWi, the service has also added a gaming layer to its gaming look. Eightbit.me is integrated with Foursquare and with Twitter to offer a game based on your check-ins.

Rather than building an app, the game has been built in HTML5, which means it's compatible with multiple devices. According to co-founder Courtney Guertin, "At launch we wanted to show the power of HTML5 and mobile devices. The entire application looks/feels native but is entirely rendered in the browser. That said, in the coming weeks we will have native applications that will allow us to give a richer experience for the user."

An interesting note: on the iPhone, you're prompted to add a shortcut to the Eightbit.me website your Home Screen before you can proceed. "Aggressive and clever," in the words of Dogpatch Labs' Ryan Spoon.

Checking in to locations will earn you coins in game that eventually you'll be able to use to customize your avatar even further. (My avatar needs tattoos.) During SXSW, checking in may win you one of 5 "EightBit Cartridge Hard Drives (what looks like an old-school gaming cartridge but is actually a 250 GB hard drive), hidden in various locations in Austin.