Privacy has been recognized as a very important issue in electronic commerce. However, many privacy techniques were not adopted and many online anonymity services failed. In this paper we propose treating privacy as a "value" that is to be added to other services to avoid the adoption pitfall. We present an architecture that anonymizes online transactions and makes them unlinkable to any customer or to each other. Our scheme guarantees fair payment to the vendor and provides efficient fraud detection and tracing mechanisms. With minimal change to existing delivery services, it can also protect transactions that require delivery of physical items. Moreover, our system could give the vendor accurate aggregate information about customers? usage pattern, which can be very valuable for its business operation. Our scheme utilizes existing financial infrastructure thus has very low adoption cost.