I saw this ads in paper about vodafone giving its prepaid subscribers the chance to get 10 rs credit balance by sending sms CREDIT (to 144 i guess). This is good thing started by VF for most of people when there balance gets over and there are no shops nearby or its nighttime and you need to make emergency calls. I myself was stucked in such situation where i wished i had at least 1 re balance at least to give a miscall. So this i think is a welcomed addon by VF. May be others will copy it soon.