As a sort of lazy effort, I've been streaming German talk radio into my ears while at work, without really listening. I'd like to think this kind of subliminal input makes a difference, familiarizing sounds and laying down thin layer by thin layer of the language foundation, but who am I kidding, I've had two years of being around the German language, and that kind of passive interaction hasn't made me fluent yet.
I've heard that television is the way to go. That still seems incredibly passive, but seems the visuals complement the audio and fill in gaps enough to really train the brain.