Movies about vampires and stoners are both extremely popular with a similar demographic. Why not do a monster mash-up? Slackula would be about a teenage vampire on an unlikely psychedelic odyssey.
Carole King and Carol Kaye were two of the most influential women in music history. Put them together in a semi-fictitious comedy/thriller about the 1960s music industry and you’ve got a smash hit on your hands.
Nunchucks are cool but they could be so much cooler.
A version of the Chia Pet/Chia Head featuring the Dude from the film The Big Lebowski. Chia sprouts could be placed on his hair and beard. Conceivably, other types of seeds could be used as well…