A system for transferring funds in lieu of cash or other data comprises portable funds transfer modules issued by a bank or other financial institution and carried by each member who may be a vendee or vendor. A first type module (20) comprises a housing (22) containing a keyboard (24) for entering data, a display (26) and a switch (30) for identifying data type. Within the housing (22) is signal processing and storage circuitry, and an optical transceiver (32, 34), coupled to the circuitry, is exposed through the housing. A second type module (42) has a housing (44) that is smaller than the housing of the first type module and includes only the internal circuitry and exposed optical transceiver (48, 50); there is no display or keyboard. The housings of the first and second type modules are provided with alignment members (36, 38, 40, 52, 54) to (a) orient pairs of the first type module with corresponding optical transceivers in alignment with each other for data transfer or (b) orient first and second type modules with each other for data transfer. In the second case, data stored in the second type module (42) is displayed in the display of the first type module (20). An optional alignment pad (56) may be used to properly position modules for data transfer. A second type of mounting pad (90) may be retrofitted to external equipment, such as an automatic teller machine (ATM), to provide funds transfer directly with a member institution.