This neat µVolume project by Rupert Hirst of RunAwayBrainz allows you to control your tunes with a nice big knob that uses a rotary encoder to get the user input. You can see the previous version in action below.
Via: Electronics Lab
“Features:
             Arduino Compatible (Atmel Atmega32u4)
             Manual volume adjustment using the rotary encoder
             (IR) Infra red remote control of volume and multimedia controls.
             Apple remote or user defined
             Visual and audible Feedback
              RGB Lighting Customization’s”