The great thing about streaming audio is its ability to free up your audio collection. Music no longer needs to be confined to one room, one PC or one audio system. Modern systems can be hooked together over a wired or wireless home network. Choosing between these depends on your needs.
If you're only planning on connecting your PC with a set of speakers in a room on the same floor of your house, using a wired arrangement is probably best. All streaming devices worth their salt feature a built-in Ethernet socket, and your PC will have one as standard. All routers have Ethernet ports aplenty and it's no harder to connect a media streamer through a router than directly to a PC.
If you intend to share music to multiple devices, or if you're going to blast music between levels of a house, wireless should definitely be your first consideration. While more costly, the benefits of being free of wires are numerous.
Some streaming audio systems act as a stand-alone media server in their own right, and we've included a couple here. They boast hard drives to store all of your content and you're not required to own a PC or central audio server to pipe music around the house. These options are considerably more expensive, but will handle all your CD ripping, library organisation and often boast speakers too.
If cost is your primary concern, stick to a wired connection. An Ethernet cable isn't the most difficult thing to disguise in a house.