USB WiFi (802.11b/g/n) Module For Raspberry Pi and more
Minicomputers like the Raspberry Pi and the Beagle Bone (more coming every week, it seems...) are making it cost effective to add some serious power to your project. Often, they'll leave out some features, but still include USB interface for expandability. In this case, if you need to add WiFi, use this well proven WiFi module.
It is supported directly by both the Raspberry Pi and the Beagble Bone without resorting to kernel recompiles, and allows 802.11b/g/n compatibility. Just make sure you have a strong power supply feeding your device, as WiFi can eat enough power to cause brownouts and resets.