Site member Adam Virgile covers a bunch of adductor exercises in his blog The Hip in Ice Hockey- Final Chapter
Make note of the comparison of supine ball squeezes ( we actually use a Pilates Ring which I think is better) and of course another European super exercise, the Copenhagen Adductor. ( this one will go down in history with Nordic Leg Curls, Bulgarian Lunges and Romanian Deadlifts).
I like Adam's set up for the Copenhagen Adductor with a band at the foot and knee. If you want to injure someone, try it with just the foot!