Trusted Computing gives rise to a new supply of trusted third parties on which distributed systems can potentially rely. They are the secure system components (hardware and software) built into nodes with Trusted Computing capabilities. These trusted third parties may be used for supporting communications in distributed systems. In particular, a trusted third party can check and certify the data sent from a node A to a node B, so that B can have some confidence in the properties of the data despite A's possible incompetence or malice. We present and explore this application of Trusted Computing, both in general and in specific instantiations.