A controversial inclusion, perhaps. But while Buffy Summers doesn't wear a cape and she can't leap tall buildings in a single bound, I'd argue she most definitely counts as a superhero. And one of the most influential superheros of the past 15 years at that. While Buffy might have grown out of cheerleading, partying and the type of Saturday night stakings at the Bronze which constituted her vamp slaying schooldays – she celebrates her 30th birthday next week – Joss Whedon's iconic series remains timeless.