I will be working from Cancun for a month and will have to call into a Canadian landline for some long conference calls, as well as have a number for my work colleagues in Canada to call me. In Europe last year I was able to use Skype for this and it was fantastic and cheap--I think I got 6 hours for $14. It looks to me as though this option is not available in Mexico though. I have an android phone and will be accessing wifi. Suggestions?