Phone for a brief trip in UK.

Hey guys and dolls,

I know that the Verge has an international fan base, and I'm hoping to get some help from those of you in the UK. To make a long story short, I'm hoping to spend my honeymoon in the UK, and I was wondering what the best way to go about getting a mobile would be considering we will be there no longer than a week.

I currently have Sprint in the states which is a on a CDMA network, and as I understand it most of Europe uses GSM. That being said, I can't use my phone overseas. I've considered the possibility of grabbing a pay-as-you-go phone and just paying for a month's credit, but wasn't sure what options were available in the UK as far as pricing and types of phones, or is that even a good idea?

Just curious what everyone's thoughts are, and hoping you awesome cats can help save me some money.

Thanks in advance!