- visual indicator - I was pretty unsure if it actually worked until I checked the pictures
- optocoupler for interfacing
- use an attiny instead of a full blown arduino
- [optional] build an antenna for 433MHz to extend the range
- intervalometer http://playground.arduino.cc/Deutsch/TimelapseDe
433MHz canon remote
One of those supposed quick hacks that turns into a complete nightmare...
I'm only logging my progress... I want to trigger my Canon camera from far away by using those cheap 433MHz one way receiver and transmitter modules.