A hacker turned an old Nokia phone into a smartwatch
I had an old Nokia 1100 phone laying around and wanted to find some way to reuse it, so I decided to see if I could turn it into a smartwatch. Taking it apart, it had a nice, hackable screen as well as a little vibrating motor for notifications. With help of a few resistors, I was able to get the screen working using an Arduino. Then with a bluetooth module and a little bit of code, I was able to send it phone and text notifications from my phone (as well as time and date, of course). A 3.7v rechargeable battery and a charging board was used for power.