Scientists in the UK have thought differently about touchpad designs: their system peeks at your fingertips to see what you're touching. It can sense when you're pushing on something and how hard, so everything —even a 3D uneven surface— could be made into a touchpad. Quite why they chose to demo this with a purring rock we're not sure. But we like it.

Apparently the team from Nottingham found it fairly easy to image the blood movements underneath your fingernails as you push on something, so their camera tracks these changes and works out whether you're touching an object and with what pressure. Try it out yourself: it's fairly easy to spot the color moving around beneath your nail.

Since the system doesn't require complex touchpad technology, it's pretty simple and cheap to produce. Good for tactile museum exhibits thinks the science team; good for whacky game console controllers think I. There's just one flaw: nail polish can confuse the camera, so naked nails it is. [New Scientist]