[citation][nom]Schnitter[/nom]There is only one reason that comes to mind this would be useful for. My billing is in USA and I tried to buy Portal 2 while on vacations in Europe. Steam detected my IP wasn't in USA and they decided NOT to accept payment. I tried visa, AmEx, PayPal, and even lost $3 to clicknbuy (they charge you around that amount to register) to try and buy Portal 2 from overseas. I finally gave up trying and contacted Support. Steam support answer after 2 days asking me for last 4 digits etc. to unlock my account to that credit card. I reply, and now I have to wait 2 more days for an answer.[/citation]Why wouldn't you just call your bank/credit card company immediately? Tell them you're on vacation and need to use your card for a purchase through Valve/Steam online. Give them all necessary info, have them unfreeze your card. It would be much faster and easier than throwing more credit cards at it or going through Steam support. I bet your Paypal is linked to one of those credit cards, that you tried to use, hence why Paypal didn't work either.
I don't see how this is a Steam issue. If anyone tries to use my credit card overseas or across the country, you can be damn sure I'm happy that the banks and credit card companies are watching out for fraud. If I am legitimetely travelling, and I have an issue, I call the bank. Not tech support for Steam or wherever the heck you're trying to use the card.