Short question: What is the cheapest way to make calls from Ireland and receive calls in Ireland while (ideally) keeping my phone number (iphone with AT&T USA) to receive calls.

Here's a more detailed explanation:

I decided to escape from work on a Weekend trip (July 1-4) to Ireland. Unfortunately, that means I will be working from Dublin on Friday July 1, so I will need to make and receive tons of phone calls on my iPhone in Ireland.

I was thinking on finding a transferring service to my cellphone, but that would still require roaming over there.

Alternatively, I can try to buy a cheap phone in Ireland and make a transfer to that phone. Is that an option?

Any ideas?

If I don't find anything else, I would end up paying $.99 per minute to AT&T (which over a course of 8 hours would be about $480).

Thanks for your help!