Airport Express audio streaming for general purpose streaming?

[generik]

As I understand you can only use the streaming capabilities of the AE for iTunes, is it possible to extend its functionality and use it for everything, such as my mail alerts, or even live TV audio audio from EyeTV?

Quite a waste that it is limited to one app because otherwise I can just hook up my speakers without having wires snaking everywhere.

 

[dcv]

There's a third party app called Airfoil that does this (I think) but I haven't tried it myself.