What device ?
SABRENT WIFI Audio Receiver (WF-RADU) is a small, low cost (< 20$) WIFI AirPlay / AirTunes receiver used to transform any audio system with a 3.5″ line-in in a AirPlay compatible device.
Under which conditions ?
No hardware modification to the device.
What to expect ?
More control on the (chinese) device. Login in a remote shell, and be able to change parameters to the device, use it as a very limited but always-on server.
What were the pitfalls ?
The CPU used is very low end (MIPS 24K V4.12, with 240 Bogomips ;-). Very low onboard DDR (32MB).