Anybody have anything more fun?
Literally, yes. The commercial sized pressurized water fire extinguishers. Which are really just giant super-soaker water pistols. I have several of those, and while the kids were still of water-fight age, in summer time we had some great battles.
Best part being that with an air compressor you can recharge them yourself as many times as you like.
Though I have to admit, CO2 extinguisher battles with mates in abandoned buildings are fun too. Or just creeping up behind someone and letting them have it at short range with no warning. (If on bare skin, no more than a brief blast!)
For actual fire extinguishing, I figure that since the power distribution boards for each building are easily accessible, I'd just kill the power first, then use the water extinguishers. But I do have one CO2 extinguisher just in case.
Also, I made sure all the garbage bins in my workshop are the solid metal variety. So small things on fire can be dumped into them. I've had this happen once, long ago. Still have that blackened bin.
A few days ago I got a nasty surprise. Was using a propane-oxy jewelers torch for some fine brazing. With the torch running for a few minutes, I thought I smelt propane. Assuming it might be a small leak around the tank valve, I flicked a lighter there to see if there would be a small flame around the valve seal. Sometimes the valve stem O-rings don't seal properly.
Woompf! There'd been a BIG leak there. Several cubic feet of flame around the tank, and a lot shorter hairs on my hand holding the lighter. Propane is heavier than air, so it flows down to the floor unless mixed up by drafts. Hence 'pool of fire on floor around tank' effect. Most flame gone in a second, leaving just a nastily large jet from the valve, but OK to turn it off by hand quickly. Fortunately there wasn't anything flammable lying around, or it could have got a bit more interesting.
Btw the door to outside was open a few feet away, so I wasn't worried about the whole room being flammable. Or I'd have shut down then tried the leak test outside.
It was a once-off; in later uses the valve doesn't leak at all. But anyway that tank gets a new O-ring next time it's empty.