MIDI Controllers (Encoders/ Livid Code) (Score 1)

MIDI Controllers are definitely the cheapest and easiest. Livid uses a Class-Compliant driver, so you don't need any drivers. The Code Controller is nice and small for Desktop Use, but has 32-EncoderKnobs all with push-buttons. One really helpful apps for MIDI Controllers on Windows is: -Bome's MIDI Translator because it'll allow you to interface your controller with programs that don't accept MIDI Input. I haven't found a Linux/Mac equivalent, yet, but I'm sure someone's done it!