Sorry for resurrecting this thread, but I'm looking for an anonymous prepaid SIM card, possibly from Europe. I'm resident in Switzerland, but I would only need the card to receive service-activation SMS. If it's possible to top it up online with BTC even better, but not strictly necessary.
Check
bitrefill.com to see if your SIM card can be topped up with bitcoin using their service. They cover many countries.
Bitrefill would be smart to also sell (where legal) unregistered SIM cards for bitcoin.