We get a lot of vendor calls here at the Browser, many of them from people with interesting/smallish ideas. But every once in a while, someone drops by with game-changer. Oooma falls — potentially — into the latter category. Launched by first-time entrepreneur Andrew Frame with a management and advisory team that includes Tivo CEO Mike Ramsay (TIVO), executives from Apple (AAPL), Yahoo (YHOO), and (somewhat inexplicably) Ashton Kutcher, Ooma promises to deliver on the true promise of VOIP: free phone calls.

Rather than providing a monthly service a la Vonage (VG), or the recently expired Sun Rocket, Ooma is offering a $399 plug-and-play box that allows users to make free domestic calls in perpetuity. That price also includes a virtual second line and broadband voice mail that’s manageable over the Web. This is a big idea for two reasons. First, it’s a nod to the growing backlash against monthly payment schemes. For $400, you can potentially knock three charges out of your monthly lineup. But it’s also interesting from a technical standpoint.

Ooma has a patent-pending call-routing system that uses both P2P (think file-sharing) technology and the traditional PSTN telephone network. In Frame’s words, Ooma has “decentralized the termination architecture.” What does that mean? Let’s say you place a call from New York, on your regular old phone, to Palo Alto. The call goes out over the Internet and reaches the local 650 calling region. At that point, it hops onto an Ooma phone and makes a local call to the desired number, without disrupting the local caller’s service. It works from a standard handset and will connect to land-based and mobile lines. International calls will be competitive with Skype (EBAY) rates. I haven’t tried the device yet. It’s still in beta with a planned launch for September. But Walt Mossberg likes it, which is a damn fine endorsement.

Ooma has $12 million in funding from Draper Fisher Jurvetson, the VC firm behind Skype. The plan is to sell the sleek $399 device and $39 add-on boxes for additional outlets, exclusively at the ooma site in the fall. Until then, the company is seeding the market through its “white rabbit” program. Beta users receive a unit and three tokens for free units to distribute to friends/family. The idea is to both establish a user base around the country, making all those long-distance-turned-local calls possible, and to create a groundswell of enthusiasm over free phone calls so that, come launch time, everyone else will, well, follow the white rabbit. “When I first heard about VOIP, I thought I’d just be able to pick up the phone and make a call for free. That still hasn’t happened,” says Frame. “The only way to provide free calling is to alter the termination architecture. Telecom has lacked innovation for the last 100 years. There’s really been a cry for innovation. This is a transformation.”