[Nav] wanted to change his keyboard mapping for one particular keyboard, rather than on each operating system. He used an AT90USBKey as a replacement PCB by soldering to all of the contacts on the key matrix. This allows him to remap the keys by following onscreen prompts.

The board enumerates as an HID device, and has a special mode which is accesses by plugging the keyboard in while holding down any key. If a text editor window is active you’ll see prompts from the microcontroller to press a series of keys. This is a routine used to learn how the key matrix is organized, and it’s your opportunity to change how each key is mapped. Since the mapping is saved to EEPROM, you can use any computer to map the keys, then plug the device into a systems that don’t offer software remapping. It could also be useful as a gaming keyboard, assuming there aren’t latency issues

As with the AVR-based arcade controller, this project uses the LUFA package to handle the USB stack.

[jayesh] wasn’t actually trying to solve any clever problems when we built his homebrew GPS tracker. He just had the hacker mentality and wanted to build something fun and useful while geeking out with electronics and software.

On the hardware side, he started with an Arduino, then added a GPS module for location detection and a GMS/GPRS module for the data uplink to his server over AT&T’s network. The Arduino uses several libraries and plenty of custom code. On the server, he worked up some wizardry with open-source packages and the Google Maps API. All of the source code and hardware details are well-documented. Put together, it’s a GPS tracker that can update a map in real-time. Sure, there are commercial products that do roughly the same thing, but where’s the fun in that? The principles here can also be put to good use in other microcontroller-based projects.

Not so long ago, mapping WiFi required a laptop, GPS, a big antenna and Kismet/NetStumbler. Today’s smartphones have replaced even this task. For those of us running a GPS and WiFi equipped Windows Mobile phone, WiFiFoFum is an excellent and simple solution, as well as a great companion for installing an AP. Start up WiFiFoFum, put your phone on the dash and let it collect the locations of the APs you find while driving around. You can then save the file in several formats: XML, txt, Wi-scan, POI Database, MemoryMap, Netstumbler, and even as a KML File for Google Earth/Google Maps. We have also found it to be a really handy tool for setting up WiFi in a large area, to help find the best home for the router which provides the best coverage. WiFiFoFum is also available for the iPhone via the App Store.

This is possible with Mapstraction, a Javascript API that works with nine mapping services and plans to incorporate more into the fold. Mapstraction has open-source features that normalize functions across the biggest services, which makes searching for map data a consistent, predictable experience no matter which service you use.

Some of Mapstraction’s current features are what you would expect: point, line, and polygon support, image overlay, GeoRSS and KML feed importing, and several others. We’re really looking forward to future versions with OpenStreetMap support. Currently Mapstraction works with only commercial mapping services, but OpenStreetMap combined with Mapstraction directly hits the sweet spot; a customizable, open source map.

[via Hackszine]