At the annual DEMO show, breakthrough technology ideas (along with some wannabes) go public: Two of the coolest hardware ideas from this year's show have unlikely names: Zink and Dave. Zink lets you print without ink, and Dave puts 10- to 20GB in your pocket for storing music and photos.

Zink Imaging's Zero Ink technology is designed for tiny printers (the company demonstrated a cigarette-box-sized device) and for printers built into devices like cell phones and digital cameras. Users just add paper and press print: There's no ribbon, no ink cartridge. The device, which has a built-in rechargeable battery, uses a pack of paper that has embedded crystals that melt during the printing process. Prints come out dry.

The company will, of course, sell the paper, at an intended retail price of about 20 cents (10p) per sheet. Zink is working with a network of companies that will later this year launch products such as a 7-megapixel digital camera with a built-in printer. The origin of the idea came from research at Polaroid, makers of those instant-print-gratification cameras of the 1980s.

Meanwhile, Seagate's Digital Audio Video Experience (Dave) drive lets cell phone and smartphone users carry tons of digital photos and music in their pockets. The wireless 10- to 20GB storage device lets you share digital files between mobile phones, PCs and other mobile platforms. Dave uses a slim, one-centimeter hard drive to trade files with other platforms up to 30 feet away using Bluetooth or Wi-Fi networking.

Seagate will begin selling the drive to telecommunications providers and mobile phone makers in the second quarter of 2007, to be resold under their own brands.

Electronics manufacturers can use Dave to boost storage capacity without increasing the size or cost of retail cell phones, and content providers can use it to deliver video files without latency or coverage problems, since the files can be downloaded to the hardware at leisure, instead of streamed live through mobile networks, Seagate says.