Airframes is a transportation (aviation, marine, etc) data aggregation service that receives ACARS, VDL, HFDL, SATCOM, and AIS data from volunteers around the world. This is similar to other efforts to collect, process, and display aircraft data like ADS-B, but with a focus on more interesting information, such as diagnostic, maintenance, and operational messages. It is under very active development and you will notice changes from day to day.
Contributing your feed allows us to make ground developing new decoders and make important statistical observations. It also benefits users of the service so that they can see more about flights as they traverse covered territories.
They're working on a REST API for participants.
Github: https://github.com/airframesio