The Internet serves our constant craving for information; the internal combustion engine let anyone efficiently do mechanical work with little physical effort; antibiotics significantly reduced mortality rates around the world.
Then there are the inventions that are the result of someone asking, "Hmm, I wonder if that would be a good idea?"
From a "onesie" that lets your baby mop your floors to a mic-shaped sponge for rocking out in the shower, these are the inventions that are more noteworthy for the fact that anyone thought of them in the first place than for what they actually accomplish.