If you like the open source work presented here, you can support me.
OpenWebRX is a multi-user SDR receiver software with a web interface.
I also maintain the sdr.hu site, which lists publicly available receivers around the world.
csdr is a simple DSP library and command-line tool for Software Defined Radio.
minidemod is a really-really simple demodulator intended to teach Software Defined Radio and DSP to newcomers: https://github.com/simonyiszk/minidemod
More about it in my talk at DCC 2015:
gr-ha5kfu is a set of GNU Radio blocks I wrote. It has some blocks that allow you to insert external processes into a GNU Radio flowgraph: https://github.com/simonyiszk/gr-ha5kfu
SDRLab is an RTL-SDR interface to LabVIEW for educational purposes.
RTL Multi-User Server is a small python script to allow multiple clients control the same RTL-SDR compatible DVB-T tuner, while all of them receive the stream of I/Q samples: