A student in my university and friend of mine wrote their Bachelor's thesis on recovering BEESAT-1, the first CubeSat launched by the TU Berlin back in 2009, after it was rendered inoperable due to some unfortunate circumstances. I vividly remember the moment when they executed the fix in orbit and it worked, they were jumping up and down in happiness. While I knew about this whole ordeal, I also found about the fun technical details while watching the 38C3 talk.

Happy to answer or forward any questions about nanosatellites, software in space, etc!