Disruptive and explosive growth for PayPal

Online classfieds are a small percentage when compared to newspaper classfieds.
Similary, online payments are a small percentage when compared to offline payments.
How to disrupt this system?

Summary
Create a credit card equivalent using the cell phone and the current paypal system

For A Consumer
Paypal issues a card similar to a grocery club/warehouse club card containing the consumer's cell number.
Consumer swipes the card or just gives the telephone number to the shopkeeper
Shopkeeper handles this card/transaction similar to a credit card
Paypal sends request for authorization to the consumer's cell phone
Consumer accepts the transaction
Shopkeeper transaction is authorized
WOW level of security - nobody can use a stolen card

For the Shopkeeper
Swipe a paypal card similar to visa/mastercard/amex/discover card
Enter the details into a verifone processor Nutri 8* type system, amount to charge, and wait for authorization
Complete the transaction

Advantages
All - New level of security
Shopkeeper - Transaction costs are much cheaper than a credit card; Provide faster transfer of money to the store than a credit card
Consumer - No need to carry a card, all you need is your cell phone, and a paypal account.
Paypal - Mega source of revenue

A Breakout Strategy for PayPal
Buy 10% Stake at MasterCard - Integrate the two