Portable USB-based monitors are a fantastic way to expand your productivity on the road, but they have a few issues. First of all, finding space to sprawl out your laptop setup isn’t always easy, and second, having a second screen you need to hunch down to look at just amplifies the basic ergonomic problems of the laptop form factor. Nex is hoping to solve both of those problems with the NexPad, a portable monitor that sits above your laptop’s screen instead of beside it. In technical terms, there’s nothing particularly groundbreaking about the NexPad screen (spotted by Digital Trends). It’s a…