Natpos SDR Software
Introduction - Usage Instructions - Download - Contact Info
Natpos is an SDR software for use with cheap SDR hardware via rtl_tcp from the librtlsdr project.
The main feature of Natpos that differentiates it from other SDR software is that it isn't limited to demodulating what is being received right now. You can click anywhere in the main waterfall and hear the signal that was live when that part of the image was rendered. It's like DVR for your SDR. If you can still see the signal on the screen, you can still listen to it.
Other than that, I don't know what to say about it other than that I like it. Maybe you will too.