I got a typical piece of spam today, telling me to buy some penny stock. The two unusual things about this spam are that it got past the gmail spam filters, and that the subject line, rather than being something like "Stock XYZ is going to go up this week!" was something like "SPAM Stock XYZ is going to go up this week!".
My theory is that gmail wants to let discussions of spam get through, while spam doesn't, and has figured out that the discussions of spam contain the word "Spam" much more often than the spam does. Worked well until now, but now the spammers have figured it out.