Today's BWOTD is one used by alot of British children:
"I bagsie that one mum"
'Bagsie' = Claim
Having said that, I have still been known to use this when faced with a variety of tempting choices, such as cupcakes!
I suggest you use this the next time you want to get a step ahead of friends or family. In the ensuing pause that will follow you saying it, you will be able to bagsie anything you want and make good your exit ;-)