This NewScientist Technology Blog post takes a look at the relative keyboard project: a solution for entering text into mobile devices which could permits to type on any touch-sensitive surface and have it recognised correctly. From the post: "Do you ever get bored of looking at the same old keyboard? Fortunately two researchers at the Language Technologies Institute of Carnegie Mellon University have a new idea - making them invisible.
They call their idea the "relative keyboard" and propose it as a solution for entering text into mobile devices. Under their scheme you could type on any touch-sensitive surface and have it recognised correctly. The only catch is that you need pretty good touch-typing skills for it to work.
Their software works out what is being typed by measuring the relative distance between keystrokes. Filtering possible strings using a dictionary makes it possible to work out what you meant.
In tests of the software, ten users typed a set of 160 words on a blank touchscreen and people varied widely in their accuracy. A few were only a few per cent worse when using an invisible keyboard, while others found it very hard to type when they couldn't see any keys.
Daniel Rashid and Noah Smith, who came up with the idea, say the relative keyboard could let you type on any surface - as long as your device has a way to know where your fingers fall. That could be possible using microphones, although I think the projected keyboards already out there would probably work better in that case.
A paper on the relative keyboard will be presented at a computer vision conference later this month."