Want to bring your business with you wherever you go? Inner Fence's new Credit Card Terminal accepts payments directly from your iPhone. According to the company's web page, the system offers just enough features so you don't have to drag a lot of equipment around with you, which makes it attractive for off-site use. Inner Fence suggests using it at Antique Shows, Art Festivals, and Farmers Markets, among other venues.

I think that's a pretty rocking cool idea, but this is not for the casual user. Using Credit Card Terminal takes a lot of planning before you can go out and get started. You'll first need to set up an account with Authorize.Net, a firm that handles the actual credit card processing.

I gave John Haycock, of Authorize.Net, a call to see how this all would work. He explained that iPhone users need to establish two accounts: a gateway account and a merchant account. The gateway account is responsible for authorizing cards in order to permit the transaction to go through. The merchant account allows funds to be deposited to a bank, providing the actual payments. You have to set these up before you can go forward.

As for the moolah involved, an Inner Fence page lays out your costs. First, you'll pay a $99.00 set-up fee. Then, a $27.90 monthly fee covers both your merchant and gateway accounts. You then pay a flat $0.35 fee for each transaction, which goes to Authorize.Net. Beyond that, the credit card company gets its percentage, which ranges between 2.19 to 3.3 percent, depending on the kind of credit card in use. This varies by whether you're using a rewards card, a sky miles card, or so forth; the page lays out the surcharges.

After that, you need to buy the program itself. Credit Card Terminal (iTunes) costs $49.99. As you can see, going high-tech sales with your iPhone isn't for the casual user; don't expect the guy sitting on the corner selling roses to whip out an iPhone to accept credit card purchases. And, since Ars didn't get to actually test out the program, there's no guarantee that transactions won't end with the White Apple of Doom™. Caveat venditor.