[Mahesh Venkitachalam] wanted to light up the dark recesses of his desk. What good is all that storage if you can't see a darn thing in there? His solution was to add LED strips which turn on automatically when the door is opened. The design is quite simple. A 2N2222 NPN transistor is responsible for connecting the ground rail of the LED strips mounted under each shelf. The base of that … [Read more...]