You should watch Canadian TV! Canadian political parties are trying to use negative ads like we do in the US, but they come out really lame. A great example is the one that begins "Stephen Harper says he's strong . . ."
I'm a big fan of dirty tricks ("Homosexuals for McGovern" is a great but archaic example), so I like to see negative ads the first time they run. But all the repetition is driving me to watch DVDs instead!