We learned a while back that the MicroUSB port on Google Glass was going to be used for more than connecting to your PC and charging the device when the mono bug and stereo earbuds were released by Google. While it's a huge deal to have these audio enhancing accessories around, especially if you're the type to wander around the house and listen to music through Glass, there's still plenty more that can be done with this little port. Enter the GlassLight, a simple flashlight add-on for Google Glass that can be voice activated.
This accessory is just about as simple as it gets. GlassLight snaps into the MicroUSB port and sits dormant until you tell it to do something. In order to have a command to issue to the accessory, you have to side-load the APK from Adafruit. Once installed you gain a simple "Toggle Flashlight" command that turns the light on and off. Since all you are doing is activating a single tiny LED back by your ear, both the battery drain and the amount of light produced are extremely minimal. In its current form you won't be using this to go for a late night stroll in the woods, but if you're elbows deep in a computer trying to replace a motherboard the added light right where your eyes are pointed is a great tool to have.
For $30 you get a decent starting point that isn't likely to be a part of your regular Glass setup out of the box, but is still a cool accessory to have in your Glass arsenal. This being an Adafruit project, you have everything you need to make any adjustments you see fit. Replacing the onboard LED with something a little brighter, or even just adding some kind of focusing lens to control the distribution of light are examples of things you have the ability to do to improve this concept and make it your own.