you can buy empty, but still receive enabled sim cards in developing countries in bulk very cheaply
So ask people to send an SMS then?
Any sources or details on that?
There's a huge mobile phone recycling industry with its center of operations in asia (Hong Kong). Old phones are traded in very large bulks and a lot of these will have their sim cards still in. I believe the buyers take the phones apart and reuse/resell components, where sims are just one type of component tha can be traded.
One of my thoughts is that there might well be an opportunity in bulk-providing SIM cards.
>> he processes SIM cards dropped off by men on motorcycles, paying a few cents for a card that would sell for $5 to $10 in the United States