Definately possible to access outside your network i.e. on the net.

I have a Belkin Router. It listens for port 81 on my IP and then passes port 80 to my empeg. I would have used port 80 forwarding but that already went to my webserver.

Definately works for me accessing tunes from work to home, though sometime the bandwidth of the tunes is a bit high. Internet radio works slightly better as you can lower than bandwidth.

Ta