Let's agree on one thing: CES is a spectacle. Giant TVs, cars of the future, internet-enabled everything. It's all here. And a lot of it is garbage. But there are always a few products that manage to push the envelope in their respective categories and change conversations. This year, we've selected 15 innovations. They include devices that will alter how we game, watch TV, exercise, and even play with Legos. These are PopSci's CES 2013 Products of the Future.