Originally Posted by Jesterhole
Call your bank and credit card companies, let them know you are going overseas so they won't cut off your card the first time you try and use it. I use BofA and it took about 5 minutes.
Turn off your cellphone cellular data. Even if you aren't actively using it, it will be pulling down from the interwebs and could end up charging you out of the ass.
I forgot about this part. Make sure you call your carrier and see what their international policy is. When we just went to Paris, I got 30 minutes and 50 text international text. They will also walk you through your phone so you don't get hit with data/roaming charges.