Nowadays, thanks to the web, it is a little easier to tell what is real and what is a spoof, fake, imposter, or just downright not true.  However before the days of omnipresent internet research it was much easier to pull off a hoax.

Things we can immediately recognize as fake managed to fool millions of people (and experts).  I mean, seriously, spaghetti trees???

Unicorns on the moon, fake tribes and crop circles, all feature in this crazy AllTimes10 list of Infamous Science Hoaxes!