Hi Little Ghostman, re the 1N4148 I have a zener diode tester which provides up to 200v Dc at about 0.3mA, and it is made from an old moving-needle type multimeter which has a 200v full scale.
I use it to see what voltage zener diodes are without having to decode their numbers or colours. It's very handy to sort zeners out to put in drawers.
When touching a 1N4148 or 1N914 diode on the tester they "zener" quite nicely at about 140-150v. By "zener" that means they start to gently break down and leak current at over 140v. They don't seem to harmed by that, at least not at the 0.3mA and exposed to 150v for a couple of seconds.