In Canberra (Australia) we recently ran a "How to use MAVProxy" workshop at the MHV workspace. We had a dozen or so people turn up and we spent the afternoon going through the software and it's numerous modules.
For those who don't know about MAVProxy, it is a UAV ground control station (much like Mission Planner). The emphasis is on portability, stability and low use of system resources. It was the ground station software used by the CanberraUAV team in the 2012 Outback UAV Challenge.
By itself it runs on the console, but can be extended via modules which provide a (basic) GUI. It works on any Windows or Linux machine (via Python) and is compatible with any UAV using the MAVLink protocol, such as the APM and PX4/PIXHAWK.
The documentation for MAVProxy has recently been updated and can be found at http://tridge.github.io/MAVProxy/