Check this out: listening to dead satellites. Or at least semi-dead satellites. These are satellites with dead batteries but with transmitters which turn on whenever the solar panels are in the right direction anyway. Some of the noises they make are weird and interesting.

I particularly like Transit 5B-5, launched 1964, for military navigation purposes. But recordings of many different satellites can be found at the link. Echos of the cold war – fitting, don’t you think, for the days surrounding the anniversary of the fall of the Berlin Wall?