I use a pair of powered m-audio speakers with my macbook air. I really wan't to remove the wires and be able to stream music. It would seem like the obvious choice would be to get the Airport Express but are there any alternative products? I was thinking of a Raspberry Pi similar to this: http://lifehacker.com/5978594/turn-a-raspberry-pi-into-an-airplay-receiver-for-streaming-music-in-your-living-room but was wondering. Are there any commercial alternatives to Airport Express?