'Ur So Gay' (2007)
Katy Perry's debut single told us exactly who she was right away. The mini-firestorm over her use of the word "gay" – which some saw as tin-eared homophobia, others as playful currency – foreshadowed the spirit of the controversies she'd spawn. Meanwhile, the video proved her affinity for that other publicity-wrangler: corporate sponsorship. The decision to orchestrate a pair of Fashion Royal dolls into playing Katy and her "so gay" ex led to a tweeny pop singer's dream come true: her own line of plastic lookalikes.