As unrepressed, unapologetic propellerheads, anytime someone takes two of our favorite things – cars and gizmos – and hacks them together, we take note. So when SparkFun's Nate decided he finally needed to get rid of the last key in his pocket, he took it upon himself to create a DIY solution.

Using an iPod dongle, a Nike+ shoe sensor, an Arduino Pro Mini (an open-source circuit board/software combo for electronic tinkerers), and far too many hours in the basement, he was able to create a key fob (or iFob, as Nate calls it) to unlock the doors on his Mazda3. Reading over his tutorial, the process isn't too complex, but it's not for the faint of heart, either. The only thing left for Nate to do is nix the ignition key entirely, so the next step is to install a push-button starter.

[Source: SparkFun via Engadget]