One of the things that piss me off immediately is the lack of common sense and logic. For example, people keep forwarding their friends these stupid emails which are just hoaxes dreamt up by some idler with too much time on his hands as he sits on the bench of some software company. This is forwarded by other "most clever" people who do not look at the email twice but just read the words "WARNING" "BEWARE" and "send to ALL your friends" and immediately set out to do just as the first idiot says.
There have been a lot of hoaxes over the years, so many in fact that there are a number of websites that research and denounce these hoaxes. Plus most major anti-virus and security companies maintain a section on hoax information on their website other than virii information. But do these super-intelligent people take the trouble to research the hoax? No. All they see is the Forward button and a list of their friends. As someone rightly pointed out person after person keeps forwarding it to all their friends and the list of email addresses keeps building up, and somewhere along the line it falls in the hands of a spammer.
I don't mind forwards with jokes and interesting things but the email about a little girl who is dying and has been dying for the last 70 years really pisses me off.