Project Tacit: Sonar For The Blind from Grathio Labs on Vimeo.

Bat vision – yes!  A very clever gentleman called Steve Hoefer has posted a bloody incredible tutorial on how to make your own wrist mounted sonar sensor, which you can wave around the place and near-instantaneously recieve feedback on how close objects are to you.  Super-awesome (and the red-neoprene makes it sleek and sci-fi looking) and so well written up, I’m tempted to try making one.  The only thing that puts me off is that it’s classed as an intermediate project, and I’ve barely dabbled with Arduino electronics projects in the past.

But it would be so cool to have bat senses on my wrist.  To point my arm out, and have little rubber-tipped motors gently press on my skin to say “To close!  Beware!”