Square, one of a few iPhone peripherals hoping to turn the iPhone into a credit card swiper, sounds promising. But how does it work? YouTube shows us!

Through its own app, Square processes a credit card, produces a receipt and even takes a signature. But as you'll see in this clip, there's one petty but fixable problem to the system—the Square dongle. Watch as Rose needs to steady the plug with his finger to swipe a card without popping anything loose.

I mention this now because I'm hoping that Twitter's Jack Dorsey and Digg's Kevin Rose—who are both behind the project (Rose just financially)—don't each have an alpine garage full of these horribly designed dongles. Beef up the casing a bit to increase its surface area against the iPhone, just as Mophie has with their recently announced credit card scanner, and everything will be right as rain. [Kevin Rose via Ubergizmo]