A couple of days ago some random spammer sent me the following e-mail:
It actually looks exactly like the e-mail notifications I receive daily from Twitter -- that is, except for the link content. Apparently they were not clever enough to mask the content of the underlying link with a random URL shortener. :) This e-mail was actually caught by Gmail's spam filter. I must say that I am impressed by the speed and intelligence of their spam detection system. It is very rare that it actually catches ham.