Some things (like a Lost episode or the freeway system) really only make sense in context. So what about our lives today is mostly likely to cause a confused archeologist 1,000 years in the future to give up in despair?
Will it be some leftover signage that they'll struggle to explain? Or will the archeology journals be full of warring explanations for our sports stadiums? Maybe it will simply be the massive quantities of little plastic shopping bags that they'll find in every home, store, and landfill that will finally make them throw their hands up and quit.
Tell us in the comments what your pick is — and give us your favorite alternative explanation that a future archeologist might come up with for it.