I keep battery acid for doing anodizing work. Nasty stuff but useful if handled properly. In fact, there are a lot of things that are nasty right under your kitchen counter. Take drain cleaner. This can be made of sodium hydroxide. Used in copious quantities to clear clogged drains. I use it to strip old anodizing before retreating. As in anything, you just need to use common sense.

Mekp is a substitute for amyl nitrate, another nasty used as a heart stimulant. Now we know why diesel guys are so energetic.