Been jonesing for a very high-powered, Android TV-based media hub? You now have a chance to do something about that craving, as NVIDIA has started selling its Shield set-top box in North America. Pay $199 and you'll get the regular Shield, whose tiny 16GB of storage makes it clear that you'll be streaming a lot of 4K Netflix videos and playing games in the cloud through NVIDIA's GRID service. You'll need to pony up for the $299 Shield Pro to get loads of built-in storage (500GB) for local content, although you'll also get a copy of Borderlands: The Pre-Sequel in the bargain. And don't worry about buying content to get started -- both Shields come with a $30 Google Play gift card and three months of Google Play Music, so you'll have something to do as soon as you've pulled off the shrink wrap.