I have previously mentioned my admiration for Fujitsu's document scanners. I was so impressed by the demonstrations I saw at Macworld Expo this past January, that I purchased a S510M scanner as soon as the Expo was over. I have not regretted it.

Although the S510M it is not a portable device, it is still quite compact. It certainly takes up less desk space than any flatbed scanner alternative.

From unpacking the ScanSnap to your first scan is just a matter of minutes. Once the one-time setup is complete, simply put a stack of paper into its feeder and press the Scan button. Then watch the magic. At a rate of up to 18 pages per minute, the pages fly through the scanner. It automatically scans both sides of a page (ignoring the back side if it is blank), effortlessly deals with different sizes of paper and even straightens out the image of sheets that fed through at an angle. When you're done, one more click creates a PDF file of the entire stack of paper (or multiple stacks if you wish). There is no easier way to dispose of the collection of papers in your file cabinet, converting them instead to a series of PDF files—as you move towards a paperless office.

If you prefer, you can select to directly print your scans, rather than save them—converting your scanner to a photocopy machine.

A couple of weeks ago, Fujitsu started shipping their S300M scanner, a portable version of the S510M. I had the opportunity to test one out. While it is significantly smaller than the S510M, the S300M is not as portable as, say, a pen scanner. You'll need a briefcase or backpack to carry this thing around. But (as I have covered elsewhere) pen scanners may be too portable to be practical.

Aside from size, there are only a few hardware differences between the two models. The portable can work directly from power supplied via your computer's USB port, allowing you to use it with a laptop when there is no other power source available. The S300M is also significantly slower than the S510M, maxing out at 8 pages per minute.

While the S510M ships with a copy of Acrobat Professional, the S300M ships with Cardiris. The latter utility converts business cards to editable text, even importing the results directly into a program such as Mac OS X's Address Book. When Cardiris works, it works spectacularly well. Unfortunately, I found that I needed to do additional cleanup at least 30% of the time, which seriously detracted from its convenience. For other OCR work, you'll need to buy additional software for either scanner (although you may be able to get Readiris via a rebate, if you are willing to deal with the mail-in rebate game).

Beyond this, the S300M is every bit as magical as its larger sibling. Before you rush out and buy either model, however, there are a few caveats you should bear in mind:

Documents are fed through the scanner via a sheet feeder. This means that you cannot use the scanner for anything that is in a book or a magazine or whatever—unless you are willing to tear it out into single sheets.

Although the scanner can print color documents up to 600 dpi, it is not ideally suited for scanning photos. The quality will be less than from a good flatbed scanner.

These scanners aren't cheap. The S300M retails for $295 (corrected price) while the S510M goes for $495.

If these caveats don't rule out a ScanSnap for you, you owe it to yourself to try out one or both of these marvels. For me, they have turned the otherwise tedious task of scanning into something that is close to fun. I find myself trying to think of new things to scan, just so I can use the ScanSnap more often. If Apple made a document scanner, this is what it would look like. I can't think of a much higher compliment than that.