I think some card companies have 24 hours phone service for you to report loss of card. Have the numbers of your cards written down somewhere. First thing noticing the theft of your card report it straight away.
The worst part is to having to replace all those cards, Medical card lah, Credit card lah, Keycard lah, ID card lah , company security card lah and also GF's photo (which you have to come up with a better excuse than being pick-pocketed).
Don't carry more cards and money than you need.
The other day I left my wallet in the office and went into a restaurant on the way home without having the money to pay for the food. Fortunately I remembered that I kept a $50 note inside my work bag.
Heheh....spread the money everywhere lah. Inside socks, inside belt, inside cigarette box, inside shoes, front pocket, back pocket and side pocket etc etc. And also carry two or three wallets. So one is stolen you've got another two?