Note exactly dangerous, but...
A couple of boss-related incidents spring to mind...
My first job, I was wet-behind-the-ears, fresh out of uni and landed a role at a local firm developing some pretty specialised HR software - a tiny five-man outfit that dropped down to two (me and the boss) and a part-timer over the time I was there. Effectively, I was the development department.
Now this was in the age of dial-up (circa year 2000). And being a one-man development team without an internet connection at home, I used to spend my lunch hours largely online, trying to keep abreast of what was going on in the tech scene - that was until my boss spotted the spike in the phone bill, and gave me a thorough bollocking for raising costs.
Anyway, that all went south when said boss picked a legal fight with a massive publishing company that even I, in my completely non-legal capacity, could see we weren't going to win.
The other incident comes from the role I went onto after that (having been out of work for the best part of a year, thanks to being stuck with niche knowledge). It was the most horrible work-from-home setup, any you were expected to be online and available via skype from 8:00am to 6:00pm. I was living on my own in a flat at this point (thank god for mortgage protection!), so I barely saw a soul most days...
Anyway, one day, I woke up one day feeling like I was about to die. So I fired up skype and called the boss. The conversation went roughly like this:
Me: "Hi, Sorry to say this, but I'm really not feeling too good today, I've got a temperature of (whatever it was) and ache like crazy, so I really don't think I'm up to working much today."
Boss: "If there was a £50 note on the floor in front of you, would you pick it up?"
Me (remember, at this point I was still trying to pick up the pieces from prolonged unemployment): "Yeah, why?"
Boss: "If you're well enough to pick up a £50 note, you're well enough to work."
Needless to say, I jumped out of that one as soon as I could...