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Just another stupid me-too handheld. Why doesn't somebody start putting BeagleBoards into a case with a 480x640 touchscreen LCD??? That, I would buy.

As for the IR receiver, Sharp electronics has full IrDA transceivers that only draw 0.1 mA, and that's the maximum drain, which presumably is when it is transmitting, not receiving. It can transmit remote control codes up to 5m at that level of power. Based on that, I would think that if an IR receiver draws 1mA, it's due to a cost/power tradeoff in part selection rather than a fundamental limitation of the technology.

While I recall a recent article detailing the etching of a functional Z80 onto glass, I question the ability to integrate large amounts of storage (comparatively) onto a flexible substrate.

The largest SmartCards currently on the market have 8MBits(1MB) of flash memory on board, plus a 16 bit CPU, plus 8KB of RAM, plus 8KB of ROM, plus RSA and DES accelerators, plus tamper and malfunction sensors. All in a credit card sized device sandwiched between solid PVC, and produced for ~$10 a unit. (You could open a lot of hotel doors with that SmartCard. ;-))

The key is that it's much cheaper to print all the circuitry in one piece rather than run wires or pins. As for the flexibility, I'm guessing that the circuitry isn't actually flexible, just the display part. If you had a piece in your hand, you'd probably be able to find a "lump" where the printed controllers, memory, and CPU are housed.

http://www.sharpsma.com/sma/products/mcu_soc/LH7A4 04_splash.htm

Many of the current MCUs are ball grid array (BGA) devices, which make them pretty hard to work with if you're not a professional, but a few can be had in PLCC or QFP packages, which means you can get an adapter board or socket.

You can also buy preassembled demo/development boards (this is the route I'm taking) and wire-up anything the board doesn't include by hand. Most of the MCUs on the market will have 32-bit memory busses (though they may not support more that 25 or 26 address lines), so you can attach just about anything you want to them.

This is exactly the kind of thing that Steve Ciarcia (of Ciarcia's Circuit Cellar) used to do: building personal computers from microcontrollers. Most of his designs used Z80 based devices, which was fine back in the mid- to late-eighties. Now, however, you can do a fair bit better.

As for speed, I don't know exactly what you're looking for, but the ARM devices can be had in speeds from 50MHz to 400MHz, and the same is true of the PPC and MIPS devices. That may not seem like much, compared to a 2GHz Pentium, but it's really quite nice.

Some good resources: Digi-Key is a reasonable source for all sorts of parts, Atmel makes some nice MCUs, programmable logic, and Flash RAM, Cirrus Logic makes some ARM MCUs and networking chips (amoung other things), Sharp, Samsung, Motorola, and AMD all make nice MCUs, Cogent Computers builds some nice development boards, and EarthLCD has good prices on LCDs and has an ARM based board in the works.

Btw, a direct link to the news article is here

As much as I love trusting the poster to have not made up a news story...here is the actual press release.