(MONEY Magazine) – DIGITAL DIGIT When I fly, I'm paranoid about losing my laptop--I don't want just anyone to see the financial info and documents on my machine. That's why I tried out the Ethenticator MS 3000 from Ethentica, a fingerprint sensor that slides into your laptop's PC card slot. Once you set it up to recognize your print--which proved easy to do--no one else can access the files on your machine. You can also program it to be your password at websites. The Ethenticator lists for $230, but I recently found it for $165 at www.buy.com.

FIRE(WIRE) SALE The 13GB hard drive on the iMac I bought just last year is already half full. So I was happy to see that an 80GB Maxtor FireWire external drive, which I can use to supplement my iMac's hard drive, lists for $399--a price I thought was missing a zero when I first spotted it. What's behind this deal? Now that Intel chips support the FireWire interface--which is 15 times faster than USB--prices are falling on peripherals that use it. That's great news if you own a FireWire-ready Mac or a Sony or Dell PC.

ALL THE PAGE While Handspring and Palm organizers have been selling like coffee at a truck stop--over 1 million last December alone--another hand-held device, the Blackberry from Research in Motion, has become the "it" gadget among Wall Street's pinstriped elite. Like other handhelds, the Blackberry has an address book and calendar that can be synched with your computer, but what makes this unit so appealing is that it's also a two-way pager and wireless e-mail device that's on all the time. You never miss a message. I wasn't a fan of early models because the small screen displayed just five to eight lines of text at a time. The latest incarnation has won me over. The screen on the Blackberry 957 fits 16 to 20 lines of text and is nearly as big as my Visor's display. At $499, the price is comparable to the bulkier Palm VII's; e-mail service from Blackberry (www.blackberry.net) is $40 a month, $46 including paging.

SPEED TRAPS I recently received an e-mail from a reader whose daughter was heading to college to study engineering. He wanted to buy her a laptop and wondered whether one with a Celeron processor would do the trick. Even though a Celeron might be fine for the majority of students, I recommended he spend a few hundred dollars more for a Pentium III machine. Why? Because it'll handle more quickly the complex mathematical calculations that an engineering student is likely to encounter.

With most PC manufacturers making processor speed a selling point--and a new generation of chips hitting the market--every computer buyer should question which processor to buy. The right answer can save you hundreds. The processor is essentially your computer's central nervous system, relaying commands as efficiently as possible. For most computer users, 800MHz of speed is enough. But with factors such as level 2 cache (the memory on the processor) and system bus (the way it talks to the rest of the computer) affecting performance as well, you can't rely on that one number. Here's my guide to your processor choices.

The budget option. For less than $1,000, you can buy a PC with an 800MHz Intel Celeron or 850MHz AMD Duron, the chip found on H-P and Compaq computers. I've used a Celeron on notebooks like the Compaq iPaq and found it plenty peppy. These basic processors are fine for word processing and Web surfing but will come up short if you want to edit videos, burn CDs or play any game more sophisticated than a kid's point-and-click game.

Today's best values. The next step up is the Pentium III and AMD Athlon. Unlike a Celeron, an 850MHz PIII chip can handle video editing, 3-D games and digital music, thanks to more cache and bus speed. The 866MHz PIII is the processor I use at work, and it's the best PC value out there.

With the December introduction of the Pentium 4, prices for PIII machines have dropped substantially. You can get a Dell PC with an 866MHz PIII for $1,200. Most buyers can skip the more powerful 1GHz PIII; you'll pay another $300 or so for a small pickup in speed.

If you're buying a Mac, go with a 500MHz G4 dual processor. With the January introduction of the faster 733 MHz G4, Apple has cut the price of Macs with this powerful configuration by $1,000.

Early-adopter premium. How about the cream of Intel's crop: the Pentium 4, which features speeds up to 1.5GHz? I'd never recommend buying a processor right after its release, and the P4 is no exception. Not only will it add at least $1,000 to the price of your PC, but it will not necessarily be speedier. Tests by tech websites and others have found that the 1.5GHz P4 is not much faster--and is sometimes slower--than a 1GHz Pentium III or 1.2GHz AMD Athlon, mainly because applications haven't yet been written to take full advantage of its strengths.