You arrive at the airport, notebook in your carry-on bag. Suddenly, you're told you can't take your laptop onto the plane. You've got no choice but to pack it in a checked suitcase.

This once-unimaginable scenario became reality this summer after the discovery of a major terrorist plot. The ban on notebook PCs aboard flights departing from the UK was temporary--but given the uncertainties of airline travel today, it could happen again.

So what's a laptop-toting frequent flyer to do? To play it safe, travelers should always "pack with the expectation that you may have to check something at the last minute," advises Steve Heiner, a longtime photographer and senior technical manager at Nikon, as quoted in a recent PC World report. That includes electronic devices as well as other personal effects, Heiner says. Read Melissa J. Perenson's "Practical Tips for Avoiding Tech Travel Hell" for more expert tips.

At a minimum, recent events should serve as a reminder of the potential hazards of traveling with a notebook. This week and next, I've got tips for protecting your data and your laptop when you fly.

Back Up Before, During, and After

Yes, you've read that advice a million times, and probably heard it from me at least 3789 times. But here's some news regarding backup options: An online data backup service called Mozy recently began offering up to 30GB of online storage space for $5 per month and $10 for 60GB. (Mozy also lets you store up to 2GB of data free.) Most online backup sites charge much more. For example, iBackup charges $20 per month for 10GB of online storage and $50 per month for 50GB. I haven't tested Mozy yet--but at that price, it's high on my to-do list. Get more info at the company's Web site.

Another service, Xdrive, recently began offering 5GB of free online storage.

For more on online backup services, read PC World's roundup review, "Store It on the Web."

Another option is to back up your most important files to a USB thumb drive. Some, such as Lexar's PowerToGo, also let you store applications, preferences, browser favorites, e-mail, and more. When you connect the drive to another computer, your files, applications, preferences, and so on are easily available. When you remove the drive, all your stuff is removed from the guest computer. It's an ideal way to back up and carry your most important data. Read Alan Stafford's take on the PowerToGo, "Take Your PC on a Thumb Drive."

Go Rugged

If your notebook is dropped or roughly mishandled in transit, any number of things can happen. The LCD can get cracked; the hard disk can be damaged; you can lose data, and so on. To help better protect your notebook from shocks, drops, and other potential travel mishaps, consider packing it in a rugged case.

For example, the new OtterBox Rugged Laptop Carrying Case can protect a notebook even in a 4-foot drop onto concrete, the company claims. Outside, the case has a protective polypropylene shell. Inside, there are shock absorbers and a Velcro surface to keep your laptop from wriggling around. IDG News Service's Agam Shah points out, however, that the case is heavy (6 pounds)--and it's expensive, at $170. Still, if you want peace of mind, this could be the notebook bag for you. Read Agam's May "Digital Gear" for his review.

Another option: Protect your notebook with bubble wrap. It's not elegant, but it's inexpensive. Just make sure you secure the bubble wrap with heavy-duty tape.

Check Your Insurance

Another precaution is to make sure your laptop is adequately insured, in case it's damaged or stolen in transit. Safeware provides insurance against accidental damage, theft, and power surges for laptops and other electronic devices. I can't personally vouch for Safeware, but I've received several e-mails from readers giving the company a thumbs-up..