Even before the Internet, there were plenty of ridiculous rumors and urban legends that went viral. There is a cure for cancer, but the medical establishment won’t release it so that it can still keep profiting off of drugs and treatments. There are light bulbs that never burn out, but the light-bulb companies would be ruined if they were sold. Oh, and there is a car that can run on water, but Big Oil won’t allow its production. 

But there really is a car now that can run on water, though its tough to say how broadly its technology can be applied.