Two years ago, before Lockitron and all of its competitors arrived, I went to college. During college, I created many prototypes of an electronic door lock that I detail below.
Lights are a necessity if you are going to be on the road at night. This applies to anything that moves–car, bike or pedestrian. I will document how I compared designs and settled on assembling a design based on Revolights for about $40/wheel. I call them SparkleLights.
I made a point-of-sales system using Arduino, a receipt printer, a 20×4 LCD and a keyboard on October 13, 2012. I thought it would be a good exercise for me because I really wanted a reason to use the Adafruit receipt printer and I would have an example of an embedded systems project that was complicated enough to require a state machine. I’ve documented all the hardware and software below.
I finally finished soldering an RGB LED ring after eight hours of hard labor with the giant Hakko soldering iron tip. It was my first SMD soldering job! The RGB LED ring was from http://blog.spitzenpfeil.org/wordpress/2012/01/11/rgb-led-ring-v2-sequels-dont-have-to-be-bad/