Depends on your goal. If you want maximum sound attenuation, you can’t really beat cheap foamies, which are rated up to about 40 dB. If only about 20 dB is good enough for your needs and you want the comfort, custom molded ear plugs are great.

A Serbian Film

This is brilliant and I am going to use it.

LOL. LMAO.

Not a book, but the Bastard Operator From Hell series on theregister.co.uk gives a decent picture, if a touch dramatized.