United States Patent: 7031939:
"Systems and methods for implementing person-to-person money exchange
Systems and methods for effecting online financial transactions between individuals or between individuals and entities such as banks, merchants and other companies. Each user accesses a fund exchange server to establish an online account, which is used to transfer funds to and from other entities' online accounts. To fund an online account, funds can be transferred to the online account from a credit card account or from another online account. To withdraw funds, money can be transferred to a credit card account or other bank account. Any user may initiate a send money transaction or a request payment transaction with any other entity provided that entity has an e-mail address.
For a send money transaction, the user sending money (payor) enters an amount of funds to be transferred and an e-mail address of the recipient of the funds (payee). The system sends an e-mail message to the payee at the address provided indicating that the amount of funds has been 'received' on the payee's behalf. The payee must then either open an online account or identify an existing online account to complete the transaction..."