Have you ever noticed how being around nutsy/negative people can make you feel nutsy/negative? Psychologists call this "emotional contagion" -- and there's even evolutionary reasons for why someone else's curmudgeonly ways can infect you.

Tatum O'Neal. Britney Spears. Lindsay Lohan. Your dear sweet Aunt Mamie. Why do so many substance abusers keep getting sucked back into their addictions -- just when you think they've bounced back for good? According to psychologists at the University of Wisconsin, it's because these folks never deal with the original core substance responsible for their substance abuse - a little substance called anger.