The DIY calculator wristwatch

If you've ever wanted the ultimate in geeky wristwear accessories, you'll want to check out the first home-made scientific calculator wristwatch.

Created by David Jones to replace a broken Casio CFX-400 calculator watch – and featured over on Hack a Day – the µWatch is just about the nerdiest thing you'll ever wear on your wrist.

Featuring both reverse Polish notation and algebraic modes, the watch was designed and built by Jones when the wrist band support on his aging Casio watch broke – and he was unable to find a product on the market that would match it for usability.

Based around a PIC board and featuring 64KB of flash storage with 8KB of RAM, it's a surprisingly powerful – if slightly bulky – unit. The screen is a dot-matrix display capable of showing two lines of up to sixteen characters, and features an LED backlight that Jones admits is "pretty dim."

The best part of the project is that all the source code – written in the MPLAB C30 language – is available under the GPL v3 open-source license, along with full schematics should you want to roll your own. If your electronic skills aren't quite up to the task, Jones is also selling the device in kit form – although the first three batches sold out rapidly.

It's not a fashion accessory that will appeal to all, but the µWatch is perfect for when you need a four-level HP-style reverse Polish notation stack strapped to your wrist. And lets face it – isn't that worth looking like a bit of a plonker?

Tempted to strap a crazily powerful calculator to your wrist, or are you hanging on for a revision with a bit more style? Has the project given you any ideas for your own custom watch? Share your thoughts over in the forums.