[davidtheprof]

I travel a lot to Europe and Canada, and was just checking out a new sim MVNO, Piranha-Mobile, and noticed that they have the best offering for Canada that I have seen in a global sim - 22c/min within Canada or back to US, and only 48c/MB for data.
looks like you have to use call-back dialing outside of the UK and US, but you can add local phone numbers, and some intriguing integration with VOIP, so you can receive calls at same numbers over wifi when connected.
Have been using Truphone, but looking at alternatives...