Over on Reddit user u/mknlsn has posted an interesting use for his RTL-SDR. He happens to live next door to a Hollywoood reality TV show production and was able to use his RTL-SDR to listen in on the wireless microphones fitted to the cast. The wireless microphones used by the production appear to be simple analogue FM modulated, without any sort of security.

We remind readers to check local laws on this sort of use, especially if recording audio, as some countries and US states may have differing laws on what can be recorded, or even listened to live. This would likely be considered private communications, so recording and sharing would definitely be illegal in most regions. 

Recently we also posted about Frugal Radio using an Airspy SDR to listen in on wireless microphones from outside a theatre show.