Can pen computing ever move beyond computer-industry curiosity and remake the way we talk to our machines? Well, hope springs eternal.

Literally. Of the 10 hours, dozen presentations, and hundreds of PowerPoint slides displayed during Microsoft's annual confab with financial analysts last month, the moment with the highest coolness quotient--a value Microsoft sometimes severely lacks--involved a spring. A Tablet PC user drew a spring holding a weight suspended from a ceiling, wrote a few equations, then, with the flick of an E-pen, set the freehand sketch bouncing in a manner dictated by the equations.

Microsoft has given the demo about a dozen times, and it apparently never fails to wow. This week, computer jocks from Brown University who developed the software, called MathPad², will show off a newer version of their creation--funded by Microsoft, of course. MathPad², which could be available later this year, can illustrate projectiles, charts, and other things that change as a function of time. Bouncing balls and colliding objects are next, say MathPad²'s developer, Brown Ph.D. candidate Joe LaViola.

Microsoft needs more applications that take advantage of the power of the pen--especially as it prepares to release Windows XP Tablet PC Edition 2005 this month, essentially version two of its pen-computing operating system. "The point I've been making and beating up on the Tablet PC group on is that no one will use them if they're featured as a new type of laptop," says Andy van Dam, a computer-science professor and VP for research at Brown, who sits on Microsoft's research technical advisory board and consults for the company. "They're slower, heavier, clumsier, not as robust, and more expensive. So what's the value? The answer, clear as day, is pen-centric applications. That's an old dream, but now's the time."

It's part of what van Dam calls the "Brown University style of interaction"--allowing creative work to be done entirely in gestures, and leaving windows, menus, and pointers for office tasks. Brown also has developed Music NotePad, Tablet PC software to generate sheet music from hand-drawn notes. Next is ChemPad. LaViola says MathPad² can work its wizardry on high-school algebra and freshman calculus tasks, including differential equations, integrals, and derivatives.

Microsoft pen computing for word processing and E-mail hasn't scintillated most users. But if Redmond funds more apps like MathPad², it just might have a killer app for its dream machine.