If you've ever used a customer support livechat service, you've probably experienced that vague, sneaking suspicion that the "person" you're chatting with might actually be a robot. Like the endearingly stiff robots we've seen in countless movies – tragic, pitiful machines tortured by their painfully restricted emotional range, futilely hoping to attain a greater degree of humanity – chatbots often sound almost human, but not quite. Their speech is awkward, the cadence somehow off. It's the online equivalent of the "Uncanny Valley," a mysterious region nestled somewhere between the natural and the synthetic that offers a disturbing glimpse at how humans are making machines that could eventually supplant humans, if only their designers could somehow make their robotic creations less nightmarish. Love them or hate them, chatbots are here to stay.