I just finished a project that I'd like to share with everyone. I built an arduino controlled lockbox from a handmade antique japanese box. The box stays locked with a latch and opens with help of a servo. 3 pots act as the code input. A button push signals when to wake up the atmega. A LED indicates whether you have the right passcode. The amtega is only awake for a 1 second if the code is right and will automatically sleep if the right code in not found within 20 seconds. Using capacitive touch sensing, if the button is touched for 5 seconds, the code will be set to whatever position the pots are in currently. The video should make it clear.https://www.youtube.com/watch?v=4egjezvDAHs
I hope you like it and please don't hesitate to critique.
Here is the link the the instructable.http://www.instructables.com/id/Super-Secret-Lock-Box-Capacitive-Touch/
If you like it, please vote for it in the "Secret Compartment & Doors" Contest on Instructables.com http://www.instructables.com/contest/secretdoors/?show=ENTRIES