A secure computing module (SCM) is configured for connection with a host device. The SCM includes a processor for performing secure processing operations, a host interface for coupling the processor to the host device, and a memory connected to the processor wherein the processor logically isolates at least some of the memory from access by the host device. The SCM generates a secure digital signature for a financial transaction and enables controlled content received through the host device. File distribution is performed from a content provider to a buyer or from a reseller to a buyer. The file distribution includes a financial transaction using secure digital signatures and possibly message encryption. The digital signatures and transaction details are communicated to appropriate financial organizations to authenticate the transaction parties and complete the transaction. The controlled content is transferred to the buyer from either the content provider or the reseller.
 The United States Government has certain rights in this invention pursuant to Contract No. DE-AC07-05-ID14517, between the United States Department of Energy and Battelle Energy Alliance, LLC.