Thanks for the suggestion! Star trackers and sun sensors are in the pipeline over the next couple of months :)

Thanks! One of next logical topics would be various devices for communication with Earth or in space (say, to a communication satellite).

Do you mean comms systems like transceivers, antenna, etc.? There's some really exciting stuff going on with phased arrays and optical comms at the moment. Software-Defined Radio (SDR) is also becoming an increasing important area of innovation for satellite comms.