Of course, the easiest and cheapest thing to do is convince a friend to loan you their unlocked GSM smartphone and buy a SIM card when you arrive in the UK, and then Dublin.

ENGADGET

We spotted a GSM Palm Pre with a Vodafone SIM card, which could mean everything or nothing.

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If you travel to Canada and want cellular service for more than emergency use, then plan on purchasing a local SIM card and perhaps using Telestial or another International virtual GSM network provider for inbound service.

FORBES: How to Save Money on Mobile While Traveling in Canada