In what it called a "small" deal worth about $300 million, American Express has announced plans to buy Revolution Money, the card-based alternative payments platform launched in 2007 by a goup that included former AOL Chief Executive Steve Case.

American Express CEO Ken Chennault said his company believes Revolution Money "has big potential," and indicated that Amex plans to take the low-cost payments platform global. The immediate effect will be to give American Express a foothold in the alternative payments arena and the technology supporting it.

The deal also -- at least potentially -- gives Amex closer business ties to several financial institutions with substantial issuing and aquiring operations. Citigroup and Fifth-Third Bank, for example, both issue Revolution Money cards and Fifth Third also includes Revolution card acceptaance in its merchant acquiring operations