I have been purchasing minutes on my prepaid cell phone, as well as other family members and friends, by shopping on Ebay for the best deal.  I no longer have to go to a store and pay retail price, plus the tax, but you really have to be careful what you're purchasing.  I use the Verizon Prepaid Wireless system and when I purchased mine, it was called "Freeup".  Now it is called "Impulse" and can be used as the same means when you're adding minutes to your phone.  THIS IS NOT A VERIZON CALLING CARD WITH MINUTES ON IT.  This is a pin number with monetary value that you add to your existing cell phone service.  Monetary values range from $15, $30, $50, $75 and so on.  I have had pretty good luck with the seller emailing me the pin number. It saves me time waiting on this pin number and it saves the seller costs on mailing the card to you.  Sometimes the seller will offer to send the card to you.  If there are sending a card to you, regular first class mail, it shouldn't cost anymore than 41 cents, not the outrageous prices I have seen on Ebay.  Also, make sure you check the seller out.  If you have questions, ask the seller.  Make sure you ask about the expiration date on the card.  Yes, IT DOES COME WITH ONE, and if you don't use this pin number by that expiration, the pin number becomes void.  Search for several seemingly good deals and then compare the auctions.  Lower than face value (the lower the better), free shipping (including emailing you the pin number), how long has this seller been doing this, and ask questions!  I hope your buying experience can save you money like it has with me !!