http://www.paytoo.com
more details here:
http://merchant.paytoo.com/
They give you card, but they also give o SIM card for use on your phone
They accept adult, i have a sponsor that use this for a while.. i don't know about the fees yet.
The demo looks pretty Sci-FI
here:
https://youtube.com/watch?v=d86eORqnYAw