The motion-control interaction controller and software will be included in new high-end notebooks and premium all-in-one PCs. Leap Motion's technology is broadly similar to Microsoft 's Kinect gestural controller, which was originally designed for the Xbox but has now sprung a bustling cottage industry of spinoff applications.

However, Kinect is oriented toward full body views, while Leap Motion focuses on the space in front of a screen. Leap Motion says its technology is much more precise, tracking movements as small as 1/100th millimeter -- smaller than a pin tip and without lag time. Additionally, Leap Motion has a 150-degree field of view, and can track each hand and all ten fingers at 290 frames per second.

12,000 Developer Kits

Leap Motion's technology was unveiled in May of last year, and 12,000 free development kits have been sent to developers who were selected from more than 40,000 applicants. As a standalone peripheral, the controller and software will cost about $70 when it goes on sale later this year.

If Leap Motion or similar technology becomes popular on Windows 8 machines, it could have a significant impact on Microsoft's strategy. First, it competes with Kinect, although Leap Motion says its technology is 200 times more accurate than anything comparable. It also means that users can skip touchscreens, or use touch or gesture as they choose. Leap Motion CEO and co-founder Michael Buckwald has told news media that his company's technology "can provide a better experience than a touchscreen " for Windows 8.

Both touch and gestural interaction have one drawback for long-term computer interaction -- arm fatigue. But, with the precise gestural interaction and an inexpensive peripheral offered by Leap Motion, full arm motion may not be required to have the disruptive effect of, say, replacing the mouse.

'Early Days' of Post-Touch Era

The arm-fatigue issue, of course, is not present in the rapidly growing field of voice-based interaction, such as Apple's Siri -- or in such emerging technologies as eye-tracking. Earlier this week, for instance, Sweden-based Tobii Technology announced it will begin selling to developers a device that allows Windows 8 users to control their computers via a "gaze interaction peripheral." A consumer version is expected later this year.

The Asus deal is Leap Motion's initial offering in the market, giving developers their first inkling of what could become an installed base. Asus has said that, with Leap Motion technology onboard, it will build software that allows free-form gesture to work natively.

Charles King, an analyst with Pund-IT, called the Asus-Leap Motion deal "very interesting," and added that we're in the "early days" of the post-touch era. He pointed out that Intel's next-generation Haswell processor architecture is the underlying technology making Leap Motion and other new interaction technologies possible.

King told us that "we've gotten to the point where the PC and Mac platform can support these kinds of features," and said that, depending on the actual applications developed, precise gestural technology could find a receptive audience in both the business and consumer markets.