Thanks for the information. I guess I should have made my question a bit clearer. I am looking to buy (in the USA) a calling card that can be easily used in Mexico that has good rates and not abusive "extra" charges. I want to give the calling card as a going away gift for some young friends who will be taking their first "out of country" trip. They will not have a computer with them.

Any ideas on which calling cards that can be bought in the USA can be used in Mexico and have good rates?