So I am sitting not in the livingroom but on my couch, listening to
www.youtube.com/watch?v=V3y-6-…, when suddenly...
BANG! A gunshot was heard through the apartment, it was really like someone firing a gun in the livingroom. I will cut this story a bit short because noone wants to read in detail all my confusion and search for the source of this noise...
So I found a suspicious metalbutton with a pin laying on the carpet and my corner (Desk, PC, PS3) is covered with some blueish crystal dust.
Turned out, a battery which I forgot to trash 3 nights ago from my mouse blew up with a BANG. The strange metalobject I found was the minuspole, it was blasted from the battery, hit the wall, got deflected and fell to the floor. The blue crystal stuff was apparently what in the old days used to be battery acid, I have no idea. Of course I touched it the whole time.
I googled and I learned, that this is actually a safety mechanism. There are two safety measures, a membrane which is supposed to open and let gas out so the pressure does not cause the battery to burst is the first instance. Should it fail the bottom gets ejected with a loud noise (Gunshot, it did not sound like it for nothing I guess). In both cases apparently you have the shit all over the place.
Before someone now says it only happens if you heat the battery or try to recharge it, nothing has happened. This desk gets no direct sunlight, the weather is shit and cold and I do not recharge things... so children, careful with your batteries!