In their forthcoming book, "The Design of Things to Come: How Ordinary People Create Extraordinary Products," Craig Vogel, Jonathan Cagan, and Peter Boatwright draw a distinction between invention and "pragmatic innovation." An invention is a technological leap from one state to another. True innovations, on the other hand, may or may not represent leaps--but they do offer true value. That is, they are marketable and profitable.

So, here's a pretty cool idea: Roominder, a service brought to the world six months ago by two young guys, Luke and Dave. Basically you register for free on the site, and then enter reminders to be sent at specific times on specific dates to yourself or others. At the appointed hour(s), the message is sent to your cell phone or email.

The idea: No more missed anniversaries. No more late fees for forgetting the credit card bill. (The service, Luke writes, represents the fruit of a lifetime of research: "Luke and Dave have been scientifically examining the forgetful tendencies of humans for over two decades, with a primary focus on friends, family members, and most importantly themselves."

How does Roominder make money, I ask? It doesn't. "More of a pet project truth be told," Luke says. "Perhaps one day we can insert goofy phrases like "Keith Hammonds rocks" (or "Coors Lite is the shizzle" or "Cliff bars are yummmmmy" etc) in the blank-space where folks type in their actual roominder i.e. they are forced to read the slogan/attention is focused there. But no ads for now."

So, what's the verdict on Roominder? Invention, or innovation? And if the latter, how can it make money?