What is the one invention that you think Mankind could do without?

I don’t mean like nuclear bombs or guns or anything as serious as that, but like a certain device that simply reeks of laziness. For me, it would be a leaf blower. They are loud and noisy, and they really serve no good purpose other than to annoy your neighbors. Sure, you can sweep leaves off your lawn or your driveway with one, but you can do the same thing with a broom or a rake. I have nothing against power tools, as I own my fair share of them, but I’d never buy a leaf blower.

What are some of the machines that people use that strike you as pretty much a waste of technology, or are simply a superfluous device with no apparent logical purpose?