Aquinas I always found holding my middle child upside down by her ankles behind my back and pretending I'd lost her (prolonged conversations with DH about what he might have done wih her and how he could have lost her again already) quite effective at keeping her entertained and restrained in boring public places. I looked like a freak but she thought it was hilarious for at least a year.
I may well test drive that!
I think we're at an age where a piggyback is a good distraction, too, so same vein.
