Apple Airport Express

Now with blazing 802.11n, the affordable Apple Airport Express is powerful enough to run a home Wi-Fi network, yet small enough to take on the road. Share your wireless network with up to 10 users, print documents, photos, and more from any room in the house to one central printer, play iTunes music through your stereo or powered speakers using AirTunes, and more.

AirTunes takes the music from the iTunes library on your computer and sends it wirelessly to any stereo or speakers in your home. All you have to do is plug an AirPort Express into an electrical outlet near those speakers, then connect them with an audio cable. In iTunes, you can choose which speakers you want your music to play on--in your den, living room, or bedroom.

If you have more than one AirPort Express connected to speakers, you can play the same music on all your speakers at the same time to create a whole-house musical experience. Plus, if you already have a wireless network in place, you can use AirPort Express to add music to its capabilities.

(Source) Amazon