Martin scared me in one of his videos, he said that a cheap multimeter can explode and he knew someone who was hurted with a plasma ball or something.
Over at badcaps.net, I see a lot of shockingly bad multimeters because I ask for them and awards bonus points (typically 99 cent variations of the 830).
However, most of the time the
biggest danger is the user. Many don't bother to read or research how to properly use a multimeter.
People are
1) measuring resistance with power on
2) they don't know difference between hot and cold ground
3) they don't know heatsinks could be live
4) they try measuring the inverter transformer which could easily be > 1000V AC
5) don't bother to read the manual and think they are experts because they saw it on youtube
6) don't remove rings, jewelry, etc
PS. I posting this while I'm only 4 minutes into Martin's T4D29. Hmm, sleep or watch the whole T4D?