This is a really simple (but beautiful) iPod dock designed to connect to old iPods (mainly Nanos) with Apple 30-pin iPod dock connector, and offers large buttons for controlling playback (play/pause, forward/back, volume up/down). It provides charging capabilities for your iPod and includes a headphone out and an optional Bluetooth transmitter to connect to your wireless Bluetooth headphones. Control of the iPod is achieved using an Arduino that uses serial lines present in the 30-pin connector to connect to the iPod and control it using Apple Accessory Protocol (AAP).
The whole schematic is shown here in the gallery. To get more details on building this (and complete arduino firmware) go to the projects github page:
Arduino Pro Mini
You will need the 3.3V version. I am using the 5V version, but the Atmega 328 isn't designed to run at 16MHz at 3.3V, so using the 3.3V board is a safer bet
push buttons of your choosing
I am using 2 different kinds simply because I didn't have enough of one kind
male 30 pin Apple dock connector
the harderst part to find. There are some available on ebay, or you can get a cheap ipod acessory and get the connector from that. You can also try getting one from a cable.
A 3.5mm headphone Y splitter cable
or just a very short 3.5mm extension if you only want one audio jack
A USB cable to connect the dock to power
For charging the iPod