[carlos_silva]

In Portugal you can buy and use a prepaid sim card without showing your ID or giving away any personal information. On the other hand buying credit is done via the bank, so you only have a few euros to spend before losing anonymity.

[bye_gmail]

It's different in different countries. Estonia, Latvia, Netherlands allow sim cards wihout IDs. Poland, Switzerland do not.

[svdgraaf]

Afaik since last year an ID is required in The Netherlands as well.

[squarefoot]

You lose anonimity in a very short time if you either:

1- Use the new "anonymous" sim card with a phone you already own and used with other sim card (IMEI matching).

2- Use a new phone with the new sim card but let it connect through your home WiFi network (IP tracking).

3- Use a new sim card and a new phone, but carry the new phone around with your main phone so that they find your second phone and number just by looking in the carrier(s) database(s) if there are any matches to the tower areas the first phone connects to.

[dazc]

Must be a buoyant market in sims walking over the border?