Oysters. Never used to be able to eat them and now I could polish of one or two dozen like it was nothing.
I also never used to listen to music with screams in it, whereas now they're in all the music I listen to. I still can't listen to a band that features no clean singing and is just screaming, but as long as the music is as good as something like Periphery or Monuments then the screaming won't bother me at all.