I collaborated with three engineers create PajamaDuty, a wearable that alerts you to a PagerDuty incident. We used a Bluetooth-capable microcontroller (IOIO for Android), LEDs, an electric motor, a USB bluetooth dongle, conductive fabric, and conductive thread. All electrical components were assembled and the board was programmed using an open source Android library. Everything was then stitched into a t-shirt using the conductive thread.
The acknowledge button on the shoulder was made using two pieces of conductive fabric separated by sponge material. Pressing the two pieces together closes the circuit. Conductive thread was used for its flexibility and light weight to connect all of the components.