In this piece we’ve rounded up five of the most common varieties of third-party operating systems, with emphasis on what they give you and who they’re best for. Some of these are designed for embedded hardware or specific models of router only; some are designed as more hardware-agnostic solutions; and some are intended to serve as the backbone for x86-based appliances. To that end, we’ve presented them with the more embedded-oriented solutions first and the more generic-PC oriented solutions last.