My ezcap USB dongle (RTL1832U/E4000) arrived from dealextreme yesterday and it took a whole hour of tweaking settings and wikipedia browsing to go from fuzzy crackle to working (and I think I understand the basics of it) software defined radio FM decoding. I started with someone elses grc file (although I can't remember who's) and tweaked it until I got to this setup.
In the top FFT you can see the station I'm tuned to in the middle and two stations on either side (they seem to be spaced every 800khz apart in Sydney). The bottom shows the filtered signal for the station I'm tuned to.
An amateur radio expert would probably laugh at me as I arrived at these settings through nothing but a bit of a rough direction and a lot of sheer luck but it seems to sound pretty good! Now I need to think of a legitimate use for this. :)