Blessedly I am no longer on many people's mass-forwarded-email lists, but I still get a few selected emails forwarded on the premise of "isn't this cool?" and naturally many of these are hoaxes and urban legends. Due to my being in IT and known as a bit of a futurist, one in particular I get every so often is the one about a Popular Mechanics article from 1954 showing a hypothetical home computer of the year 2000:
I recently got a copy of this from, of all people, my boss. It's hardly the first time I got one in my work email. I immediately sent back a brief response saying something like, "that's funny, though the image itself is a hoax, but it's still amusing" -- and I didn't even link to the relevant Snopes page. To my mind, I showed incredible restraint in only saying that little, but most people would probably say that I shouldn't've said anything. Correcting your boss is not good tactics and should be reserved for times when it's vitally important.
But I can't not debunk this kind of self-propogating misinformation. I don't know if it's a matter of principle or if it's a simple compulsion, but either way it's irresistible. And inevitably I get defensive. The recipient of my debunking is likely to get defensive because I'm pointing out how they fell for a hoax, and their reactions could range from umbrage to silence, but you'll never get back a "thanks!" for showing them the truth. And I anticipate that and feel like I have to defend my actions, and then I get indignant: why should I have to defend the act of debunking misinformation and stopping the flow of bullshit that dilutes the value of the best information distribution and collection device ever built by humanity?
Nothing good comes of this; it's no-win. Letting the hoaxes spread unchecked is bad, but there's no way to stop them that doesn't bring bad feelings both to me and the person I'm sending off to Snopes, and maybe even impair whatever relationship I have with that person. I just dread getting these things now.