I have been intrigued by software defined radio (SDR) for some time. The basic premise is that many of the components of a radio that were traditionally implemented in hardware, can now be done in software. This includes filters, mixers, amplifiers, modulators, etc.
RTL-SDR came about when someone discovered that with a little software, a cheap USB TV dongle can be used for wider SDR, and I had to see this in action. After a little research, I decided to buy a Terratec T-Stick Plus (sheesh, the price has risen dramatically) because of the chip used. This particular dongle has an Elonics E400o chipset, supposedly one of the better choices.
The software was a bit of a beast to set up (first I tried on OS X, big mistake) but I finally have something going. I haven’t fiddled with it much yet, but I can’t wait to try and put that RF school-learning to some proper use.