Who wants to buy Tesla Motors' new four-door, all-electric sedan, the Model S?

Well, 520 people have said "yes!" and forked over deposits since the startup carmaker unveiled a prototype Model S last week.

All the publicity from the Model S unveiling apparently has produced results. The number of reservations so far is higher than the "optimistic internal projections," said Tesla's CEO Elon Musk in a statement Wednesday. "Weird Al" Yankovic has reserved one, according to his Twitter feed from earlier this week.

The company doesn't plan to begin producing Model S until the third quarter of 2011, and it expects to produce 20,000 cars per year. San Carlos, Calif.-based Tesla is waiting for a $350 million federal loan to build the Model S factory, which would be located somewhere in Southern California (see Tesla Will Build Model S in SoCal).

Unlike the two-seater, $109,000 Roadster currently being produced by Tesla, the Model S is designed to appeal to families and anyone else who is willing to pay a premium for all-electric vehicles (see Can Tesla Impress the Masses). Because of the hatchback design, the Model S can fit five adults in the front two rows and two young children in the rear cargo space (good for two child seats). The motor and other key components that make the car move are located across the bottom of the car, so there is cargo room under the hood as well.

The starting price for Model S is $57,400, and that will get you a car with a 160-mile range. You can pay more for larger battery packs with a 230-mile and 300-mile range, but that will cost you more. Tesla hasn't disclosed how much more you'd have to pay for the better batteries.

The company said the car is really cheaper than its sticker price. Here is the pitch: After you factor in the $7,500 federal tax credit, the price would drop to $49,900. Musk said the cost of charging up a 230-mile battery pack is roughly $5, so you will save on fuels over time. The cost of owning a Model S is really similar to the cost of owning a $35,000 gasoline-powered sedan, he said.

You can plunk down $5,000 for a regular Model S or $40,000 for a "Signature Edition," which is supposed to come with some nifty features that Tesla has yet to disclose. The company plans to make 2,000 of the special edition cars - half of them for the U.S. market and the other half for Europe.