I love the fact that my cable box now doubles as a DVR and I never have to miss another TV show. Or put pen to paper and write an actual letter—or bang away on a typewriter. It's nice that I don't have to carry a camera, a laptop, a walkman (CD player?) and a phone and that I can have a video conference on the same device. Technology, improving over previous techniques... I'm down. It's what EDM culture is all about.
Have you seen the Griffin DJ Cable? I'll give them the fact that it does improve on the concept of DJing with your iPhone or iPad by allowing you to cue your next track selection in the headphones while listening to the PA—aka what everyone else is hearing.
Griffin’s DJ cable is wired to enable the Split Output function in Algoriddim’s popular DJay and newly launched VJay App. With Split Output mode enabled, DJay sends the master output to the left channel, and the cue output to the right channel. I suppose if you're an aspiring DJ on a budget this will let you grasp the mechanics of DJing, get your feet wet by playing some house music at home. The idea of using this in a professional setting is, well—as much as I love technology—a novelty at best. A $20 novelty item I'm happy to buy, tho… nothing wrong with playing around with something like this at home—it's a toy after all.