The Sony PRS-500 is more of a digital book than a pure personal digital assistant, but it provides the capability to carry documents with you wherever you go in a very readable format. This PDA device supports Adobe's PDF files and RTF text files so you can load it up with all the office reading you need to catch up on during your cross-country flight.

The PRS-500 features a six-inch screen, so there's plenty of room for text at a sharpness of approximately 170 pixels per inch (the full screen resolution is 800 by 600). For those of us who feel the need to squint at small words from time to time, you can magnify the text up to 200 percent. Sony likens the screen to "electronic paper," and we have to agree: it's easier to read on the PRS-500 with its unique E Ink display for extended periods of time than it is on other LCDs.

The main drawback about the screen is the lack of a backlight. That means you'll need to use the device in a well-lit environment to be able to view it. While that's a bit of a pain, it also means that you get great battery life. The device draws nothing from the battery to display a page--just to change it. And Sony says you can get up to 7,500 page turns on a single charge. That lets you read a lot of books or view a lot of documents before having to plug the PRS-500 back in. And you can recharge via the included AC adapter or the USB cable while the PRS-500 is connected to your PC.

The PRS-500 is about the size of a paperback novel, except only half an inch thick. Weighing in at nine ounces, it's heavier than a typical PDA, yet still light enough to port around in a briefcase or laptop bag easily. In addition to viewing documents on this PDA device, the PRS-500 can also display photos. They'll be in grayscale instead of color, but the unique screen format gives the images a pleasant soft look to them.

The PRS-500 can also play MP3s, although its memory is limited to 64MB, meaning you can't to carry too many songs on internal storage. But it features expansion slots for both SD and MemoryStick flash memory cards, so you can make the storage as large as you need.

This PDA can also handle online RSS feeds. There's no wireless connection to the Internet, but if you download RSS blogs, news, etc. to your PC, you can transfer them over to the PRS-500 so you can read them on the go.

Our biggest beef with the PRS-500 is that page turns are quite slow. It doesn't matter as much when you're reading, but when you're moving through menus at a snail's pace, it can be a bit frustrating. The Sony PRS-500 isn't for everyone, but if you've got niche needs for a personal digital assistant, this unique Reader does a lot more than let you carry along your favorite eBooks.

Pro: Excellent display, great battery life
Con: Slow page turns

Warranty
90 days, labor; one year parts