I know a lot about a few things - mostly useless things.
It is a very sad thing that nowadays there is so little useless information.
The world needed more fireworks- especially now that there was going to be a shortage of beautiful, useless things.
Emperors are vain and useless things.
It is the useless things that make life worth living and that make life dangerous too: wine, love, art, beauty. Without them life is safe, but not worth bothering with.
The acquisition of knowledge is always of use to the intellect, because it may thus drive out useless things and retain the good. For nothing can be loved or hated unless it is first known.
Sanity? Sorry, but I don't remember having such a useless thing in the first place.
Only useless things are indispensable.
I'm fundamentally a busy person; I spend my time doing useful things and profoundly useless things!
Many people are busy trying to find better ways of doing things that should not have to be done at all. There is no progress in merely finding a better way to do a useless thing.