It's true that most homes have a WiFi network. They allow everyone access to the Internet, no matter where they are in the house. Streaming stereos and devices that allow you to stream content from the Internet are becoming more and more popular, however this is a great hack to cheaply make your own.
P.C. was outfitting his home with Airport Express cards so that he could stream music from iTunes. While he was doing so, he wondered about how he would be able to get his tunes onto the patio. He thought about making a portable Airport Express/speaker combination that could be taken outside of the house, plugged in, and stream iTunes anywhere.
He used an old router, Boston Acoustics speakers that he got on eBay, and an Airport Express card. Since his old router was only wireless G, he didn't need to bother with the latest Airport Express wireless N cards. His total cost for this build was less than $100. He basically put all of the devices into a cardboard box, along with an extension cord so that the Airport Express card and the speakers could be plugged in. He jury-rigged the rest using some duct tape and foam padding so that the whole package is somewhat secure.
A small hole was made into the box so that he could ascertain if the Airport Express card had picked up his home's WiFi signal. The holes show the lights of his router's LEDs, which tell what's going on. Red is bad, green is good! That's it. You can just port this thingamajig around and it will stream your tunes.
Naturally, you can refine this idea by making a nicer box out of wood. A wooden box or a custom metal box would probably be the best. You'd basically just have to cut out some parts that would allow you to let the sound of the speakers out. Alternatively, you could use some fancier cardboard boxes, the ones that are used to store things in homes. You'd have to hack it so that you could carry it around, but either way, the resulting streaming boombox would look a lot better. Also, better speakers would easily make this boombox a whole lot better sounding.
Another option involves refining this build even further, like the one we have shown you in the photos. It's basically the same idea, but just with some more refinements. The Palm smart phone serves as a remote for iTunes.