CES hasn't started, but Vegas is already overrun with tech companies eager to show off their products. Just after some of the major players at CES teased their goods at CES Unveiled, Start Up Debut kicked off at the Bali Hai Golf Course and Country Club. We saw numerous start ups at the event, but one that caught our eye was Lamassu, manufacturer of the smallest, least expensive Bitcoin ATM on the market.

The company was founded by brothers Zack and Josh Harvey, and the machines cost between $4,000 and $5,000 depending on how many you buy. We caught up with Josh to find out just what makes the Lamassu tick. "Our ATM started out based on Raspberry Pi," Josh told us. "That was the beginning. Just the prototype,” he adds. Now? "It's actually a Nexus 7." We asked Josh could we take a peek inside and, sure enough, that touch screen display you see on the front of the unit is actually a Nexus 7 mounted inside the case.

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Google's tablet is running a custom version of Linux that allows people to scan a QR code on their phone to deposit money to their Bitcoin wallet. Josh demoed the machine for us right there, and it's surprisingly easy. Though there are regulations to deal with in every market, Josh said people tend to catch on fairly quickly once the machine is in place, since it's a fairly intuitive process.

Lamassu just shipped their 100th ATM; the units are made in Portugal now (as opposed to the Harvey garage). They started shipping about three months ago with locations including Helsinki's central train station and a Subway location in Bratislava. There, customers can actually pay for sandwiches with Bitcoin.

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