software defined radio

I read this article on software defined radio and once again got excited about it. The only problem is that you need a very expensive ADC to pick up FM or HDTV.

If software defined radio ever becomes really common, maybe the price of the hardware will drop. It seems to me that an ADC is such a horribly useful piece of equipment that every computer should come with one. It's refreashing to see that the free software sommunity is so far ahead in this game.

If anyone I know has an old ADC card laying about and wants to work on building something cool, tell me.