VPMage
From FreeSpace Wiki
VPMage is a fairly powerful *.VP Editing tool. It is meant to be a utilitarian tool for mod or source code developers to create and edit VPs. It doesn't have the scripting features of Kazan's command-line VPmake, or the preview features of VPView, but it can be used to extract and edit files in a VP, as well as merge multiple VPs, files, and directories to create one VP.
VPMage works by adding a list of all the files and directories into memory, and then copying the data they contain to a VP once it's built. If any files are extracted/edited, they are saved in a temporary folder of the hard disk, in the same directory as VPMage. This folder is deleted after VPMage is closed.