Programs like THERBAL, FlowBal, FactSage, and Metsim often produce results in inconvenient units (such as a volume unit for gas when mass is desired). MMV-C is an Excel add-in that converts these stream units from one set of units to another (SI to AES for example), and from one unit of composition to another (absolute moles to mass %, for example). MMV-C also gives the element flow of a stream, and can mix the flow of multiple streams to give a single stream. Another capability is the conversion of a gas stream composition to partial pressure values.
MMV-C is available for $10