Radiosonde Decoding
Over on his blog, nerdsville has posted about his experiences with decoding Radiosondes, a.k.a Meteorological Weather Balloons using his Funcube Dongle, which is an SDR with similar capabilities to the RTL-SDR. Using a program called SondeMonitor he was able to produce graphs balloon sensor data such as temperature, pressure, humidity and altitude.
If you are interested in decoding this type of thing we also have a tutorial on this topic available on our site.