One part of having achieved a personummer is introduction to the Swedish medical system. I've received two letters telling me when I have appointments for a mammogram and cancer screening. I appreciate the pro-active nature of this system, but one of the appointments is while I am in Arizona and the other for a test I don't need.
To cancel them, you need to log into an online system.
To log into the online system, you have to verify who you are, through a regular cell phone # (which ours isn't quite) or through an automatic bank ID number (which we can't get yet because we don't have a regular bank account).
We ordered a passcode, which is supposed to work-- tried it, but then you have to verify it through your cell phone, which doesn't work while I'm in the US.
There are some things about international living that are great. Sorting out passwords in Swedish is not one of them!