The advantage of a built-in mobile broadband adapter is that it's one fewer thing you have to carry around. And ostensibly the manufacturer has built a better antenna by using the laptop's case to carry a signal. These cards can cost any amount from nothing to $300, depending on a carrier's subsidy and your term of commitment.

Technology changes rapidly in the cellular world, though, and an integrated, usually mini-PCI-format adapter is hard to upgrade for faster speeds. Such adapters are rarely user serviceable, and even laptop makers might not offer a swap-out program.

Currently, the Sprint and Verizon EvDO networks run at Rev. A, but some laptops still offer modems meeting the previous Rev. 0 standard. Sprint is rolling out WiMax starting this year, and that will mean a different PC Card. And AT&T's HSPA technology has already seen one boost (in the upstream direction); the downstream side could double in the next year to match top European speeds. (The one exception to the speed-enhancement trend is Qualcomm's forthcoming Gobi technology, which can switch between EvDO and HSPA; Dell will offer a Gobi option this fall.)

Our verdict: With the potential for enjoying faster service and avoiding outdated hardware, buying a stand-alone card--perhaps the USB type, for shuttling among computers--doesn't cost any more than choosing an integrated modem, and provides more flexibility.

Draft-N Wireless

Wi-Fi continues to evolve, but its latest incarnation, draft-n, is likely the fastest flavor we'll have until 2012. Laptop makers were early adopters of this version of the IEEE 802.11n standard, which may change slightly and require firmware and driver upgrades as it moves toward full approval in 2009.

Most business laptops still include 802.11g -- the 2003-era standard that was itself a big speed boost--as standard equipment or as a downgrade option to reduce cost during configuration of a purchase. Upgrading to draft-n adds from $15 to $40 to the cost of most companies' laptops. (The one notable exception is Apple, which standardized on draft-n for its laptops in October 2006.) The biggest advantage of a draft-n adapter is that transferring large files between similarly equipped computers or to and from a high-speed corporate (or even gigabit SOHO) network takes one-third to one-fifth the time as the task does over 802.11g.

Our verdict: Rather than buy a laptop with a five-year-old standard built in, ride on the cutting edge and select draft-n. The modest cost gets you a substantial speed boost, and futureproofs your laptop for a few years.

Fingerprint Scanner

Once a feature for people working in high-security jobs, fingerprint scanners are now commonplace, included in most premium business laptops and available otherwise as an inexpensive add-on. Lenovo, for instance, charges a bit over $20 to swap its touchpad with a fingerprint reader; Dell asks for $30 to add the device to laptops in its Latitude line.

Depending on the laptop, a fingerprint reader might be tied in with boot-time firmware to prevent a computer from starting up without a valid fingerprint. It may also safeguard Windows log-ins or replace passwords for online services and encrypted virtual disk mounting.

Our verdict: Just about any business or individual would benefit from having one of these readers, especially considering the negligible expense. But make sure that the reader and the laptop configuration combine for the particular protection features you need.

Hardware Drive Encryption

The biggest mainstream security story of the last few years concerns the theft of laptops containing credit card numbers, credit history, Social Security numbers, and other data belonging to consumers, veterans, and company employees. If only the victims had employed encryption, right?