(FORTUNE Small Business) – During a recent layover in Phoenix, I checked my voicemail and heard a doom-laden message from one of my employees: "We've got a serious problem here!" he said. "Call me back as soon as you get this." I couldn't dial my office number fast enough.

Our company, Blue-Sky Solutions, provides graphic-design and photography services for clients all over the country. It turned out that our largest and best-paying client, a Maine-based sports company, needed packaging and store-display designs for one of its products, a practice weight that straps onto hockey sticks. The client had received an unexpectedly large order for the item. Production was scheduled to start immediately. In order to avoid crippling rush charges from the packaging contractor, my client needed final designs within 48 hours.

I was sitting in an airport lounge in Phoenix. The client was in Maine, and my designers were back at our office in Brick, N.J. We needed to collaborate on the designs virtually, because we couldn't be in the same room. Luckily, all of us were equipped with an interactive graphic-design tool that allowed us to create a digital workspace online.

These gizmos are known as whiteboard-capture devices. The two main commercial versions are e-Beam System 3 from Luidia and Mimio Xi from Virtual Ink. Both devices consist of software plus a small gadget that sticks to your whiteboard. Using ultrasound technology, the gadget captures images drawn on the whiteboard with an electronic erasable marker, and sends them to your computer. If you don't have a whiteboard, any flat surface will do, such as a window or a tabletop. Both devices run on batteries, come in USB and Bluetooth versions, and sell for less than $800. (The e-Beam System 3 retails for $749.95, and the Mimio Xi for $799.)

I've tried both products, and in my opinion the e-Beam has two major advantages over the Mimio Xi, particularly for road warriors like me. One is size: At 7.5-by-4 inches, the e-Beam transceiver fits easily into a laptop bag and weighs less than a pound. By contrast, the Mimio Xi unit is two feet long and weighs in at a husky 2½ pounds.

The e-Beam's software allows remote users to collaborate right out of the box using the Internet or an intranet. The Mimio Xi requires third-party software for that purpose. Because remote collaboration is my main reason for using a whiteboard-capture device, that's a big differentiator.

On the other hand, the Mimio Xi has onboard memory that allows it to capture the equivalent of 20 to 30 pages of text and drawings (according to the manufacturer) without hooking the system up to a computer. The e-Beam has no onboard memory, so it works only in conjunction with a PC.

Both devices allow you to create new pages, save versions of pages as you go, display your presentation in thumbnail or slide-show format, and change the thickness and color of pen lines as they show up on your computer or handheld device. You can save whiteboard files in several formats, such as PowerPoint and HTML.

Bottom Line: The E-Beam is a better road device and a better remote-collaboration tool. I use my e-Beam about twice a week for brainstorming sessions and offsite presentations. I don't always bring the hardware along on road trips, but the software is with me 24/7.

Luckily, I had brought the hardware along on this trip and was ready when the crisis struck. I bought a day pass at an airport club that had a Wi-Fi connection. My designer set up an online e-Beam session, and we all got on a conference call to discuss the design concept that was taking shape on computer screens in three U.S. states. We finalized a nifty design in one hour and made the client's production deadline with time to spare.

Because the collaboration happened so smoothly and quickly, our charges came in well under the $2,500 that the client had budgeted for design. The quick turnaround saved our client more than $10,000 in rush production charges. And the best part? The client was pleased enough to steer $20,000 in new business our way.