Are you interested in receiving and decoding telemetry from amateur radio satellites? Then check out this excellent article by Jan PE0SAT called Unix TLM (Telemetry) decoding, where Jan gives a description of his setup.
In his Linux setup, Jan uses Gqrx as SDR front-end and Gpredict to track the satellites. As we wrote earlier, Gqrx has a Hamlib-compatible TCP interface so that we can use Gpredict to adjust the receiver frequency with Doppler corrections.
Jan also takes advantage of the Audio/UDP interface in Gqrx as well as the audio routing capabilities of modern Linux desktops to route the demodulated audio from Gqrx to external decoder applications.
All in all, this is a very nice setup that demonstrates well how Gqrx can be hooked up with external applications to get new functionality.