SAN DIEGO – There are still those rare tech gadgets that elicit oohs and ahhs from even the most jaded gear hounds. PlasticLogic’s display is one of those. The size of a sheet of paper, about three-eighths of an inch thick and weighing 13 ounces, the device is a gray-scale screen – which can store thousands of documents for reading and annotating.  Picking up the prototype here at the DEMO conference is more like hefting a piece of thick cardboard than any electronic display you may have tried.

And it is mostly a display. Crisp images and text in grays and whites are easy to read, and with just a little lag, scroll from page to page easily. While it isn’t ready yet, ultimately you will be able to add notes and sketches to PDFs, CAD drawings, spreadsheets and text documents. The documents will synch from a computer via Bluetooth, Wi-Fi or a wired connection. Lithium ion batteries power the display. An obvious upgrade in future versions would be a color screen.

When you see it, you immediately want it to become a tablet PC, something that has both input and output. But replacing the PC is not what PlasticLogic is trying to do. “We want to replace paper,” says Steven Glass, head of user experience for the Mountain View, Calif.-based company. “The point is to be able to deliver this at a price more in line with the current crop of e-readers like (Amazon’s) Kindle which sells for around $349.”

The company, whose technology was initially developed at Cambridge University, is focused on doing in plastic what today is typically done in silicon. Why do that, is an obvious question when the chip industry has amassed such expertise in turning silicon wafers into the guts of all sorts of electronics.

The answer, according to Glass, is the relative cheapness of scaling up a plastic display factory versus building a chip-making plant. In the end, making semiconductors from plastic, with its low temperatures and quick production time, could be 40% to 50% cheaper than using silicon.

PlasticLogic is building a factory in Dresden, Germany (which goes live in ten days to produce these displays) for the low hundreds of millions compared to the billions it takes to build a typical silicon fab. The company has raised $200 million from an assortment of strategic partners and investors. Expect PlasticLogic displays to hit the market by the middle of next year.

So will you want one? If you are at all curious about the Kindle you should check it out. But it may have more appeal in the office than on the beach – you can see lawyers and information workers using the displays instead of carting around reams of documents.