This project is solving the Virtual Ground Station App – Global Crowdsourcing of CubeSats challenge. Description
With a RTL-SDR dongle costing no more than a 10 dollars or less one can receive live satellite data but only when the satellite is visible to you. The same concept of sharing that data globally (like http://flightradar24.com does with data coming from airplanes), it should be possible redistribute the data back to the participants and in the process get a a global sensor network for telemetry-data for free.
License: MIT license (MIT)
Source Code/Project URL: https://github.com/marcelmaatkamp/realtimesensoreventprocessplatform