Have a spare iPhone 3GS or iPod Touch (2nd gen or higher) lying around? Why not get some use out of it and turn it into an AirPlay receiver. Using a jailbreak hack you can stream music from your iTunes to speakers connected to a jailbroken iPhone or iPod Touch. It's a perfect for solution for a summer party and is a neat hack that will allow you play the same music throughout your home on multiple speakers.
Jailbreaking may seem a little daunting when it comes to a device that you use and rely on everyday, but if you have a spare iPhone or iPod Touch it can be a fun and rewarding project. Additionally right now at 4.3.3, jailbreaking is easier and since we know that iOS 5 isn't coming out until the fall, now is as good a time as any to try this out. Redmond Pie has a great how to that will show you how to jailbreak your device. After jailbreaking, you can create an AirPlay receiver using an iPhone 3GS (or higher), 2nd gen iPod Touch (or higher) or an iPad. You can either pay $4.99 and download AirServer from jailbreak store Cydia or do it yourself for free using this how to.
Now you might be asking why you shouldn't simply use a bluetooth receiver like this to stream music wirelessly to speakers. The advantage of using an AirPlay receiver is that you can use iTunes to play to multiple AirPlay receivers all at once. For instance, I have my iTunes music playing on my iMac in my room, my Apple TV in the living room and an old iPhone 3GS permanently connected to a Jambox in the kitchen. It's a pretty seamless setup so everything plays simultaneously throughout my home without any echo. It's great for when I want to listen to music in multiple rooms or just feel immersed in whatever I'm listening to—more importantly though I've found it to be great for when I'm entertaining guests or hosting a party. The main reason I wanted to set this up was for an upcoming 4th of July party at my apartment, so that I'd be able to play the same music from iTunes on both my living room computer speakers and my 5.1 speakers at my media center. When guests head to the kitchen they'll be able to hear the same music from my Jambox. All in all it's an interesting little hack that might be fun to try at your next house party or summer barbecue.