I wasn’t even aware such a thing existed until my friend Rob told me about it. The one I bought is a discontinued model from D-Link (the DSB-R100). You plug one of the antenna’s connectors into a USB port, the other into the Line In port on your sound card.
I found out the hard way that it’s very important to completely ignore the software that comes with it. After installing the driver and radio software on the PC, my machine crashed. Every other time I tried to start up the radio software, it would reboot my machine. So I followed the two pieces of advice I’d been given earlier:
1. Install the GemTek drivers instead
2. Install Radiator
The drivers and the software are both freely available. Now everything works like a charm. I’ve got the same FM radio presets on my PC that I’ve got in my car. The really interesting feature of the software is that it allows you to schedule the recording of broadcasts in WAV or MP3 format. You can record from other sources as well (directly from line in, microphone, CD audio, etc.) which I haven’t tried (yet).