Alice had a fun experience while trying to buy Xbox points. It seems the way Microsoft handles points purchases causes credit card companies to freeze the card preemptively...

"Oh yes, Microsoft's Xbox division pings the card from Luxembourg, and you're not in Luxembourg, and they also do this thing where they charge your card a dummy £1 transaction to test to see if the card works. This is what criminals do, so as it's from a .lu domain, it's done on the internet, and they do this dummy charge, it automatically shuts the card down."

Man, that makes my UI hassles and the fact that I couldn't revive my Xbox 1 Live account on the 360 pale into insignificance.