A Halloween decoration I built in 2015 that runs for a week off of a single 2032 battery. The idea is to put a bunch of these into your empty bird feeders, bird houses, and other places vacated by birds in the fall. When the sun goes down they all start a sinusoidal PWM "glow" of the two LEDs with a random (sorta) wait to keep them from getting in sync. The effect is meant to invoke a yard inhabited by demon "birds of the damned" ready to swarm down and devour the unsuspecting trick-or-treater.
One of these years I'm going to do a run of PCBs with OSH Park to get a large flock of these in the yard. I'll post the eagle CAD files and a video when I do.
I'm also particularly proud of my Lego pogo programming rig. That's right, the BoD board fits into that Lego contraption you see in the pictures and the pogos hit all six pins needed for the AVR SPI programming protocol. I used a Lego window, drilled holes in it to take the pogos, and fixed them in-place with epoxy. The window even lets you see that the pins are making the correct contacts. What can't you do with Lego, I ask?
Here are some details:
MCU – ATTiny13
firmware – Github
photo sensor – Maxim 4409
substrate – Surfboard