[vel0city]

I'm not necessarily talking about getting shocked (which can still end up being bad), I'm also referring to the fact a lot of those 120V circuits are probably only protected by something like 12-15-20A of circuit breakers that might take a while to actually blow and unless you're in a kitchen or a bathroom or whatever probably don't have GFCI protection. Messing something up can quickly lead to quite a fire.

[theamk]

Lots (all?) old devices have input fuses, and often those are right next to the plug. So most of the mistakes will cause this fuse to blow (unless you recklessly short it, or drop a screwdriver in the unlucky spot)

That said, even something as simple as surge protector power strip is going to have a nice and fast circuit breaker in it. If you want to get fancier, get a GFCI extension strip from home depot. And if you get an isolation transformer, it'll certainly have a fuse or a breaker.