[PhotoJim]

Unfortunately, there aren't yet any GSM/UMTS-based prepaid data options for Canada that really make any sense. Some Canadian providers are starting to provide reasonably attractive Canadian roaming if you buy a specific Canada/US data package; perhaps your US provider has something similar. (Only in the past year or so have any US carriers implemented affordable data on prepaid, and Canada is a little behind.)

I'll let the others comment on Germany, but odds are good that there is something quite good there. Most European countries have very affordable prepaid data plans.