"Nothing, I Guess."

From Wikipedia:

Heinrich Hertz did not realize the practical importance of his
 experiments. He stated that,

"It's of no use whatsoever[...] this is just an experiment that proves Maestro Maxwell was right -- we just have these mysterious electromagnetic waves that we cannot see with the naked eye. But they are there."

Asked about the ramifications of his discoveries, Hertz replied,

"Nothing, I guess."

Hertz died at age 36.