1. A computing device for content indexing of data files being archived, the computing device comprising: one or more processors and computer-memory; an executable indexer that is configured to, in the course of one or more data files being archived to respective archive copies, index the one or more data files according to content attributes, including at least one of: textual content, picture content, video content, and audio content, wherein each archive copy is stored offline relative to a user computing device; the executable indexer further configured to: (a) associate content attributes with respective smaller portions of each archive copy, (b) for the one or more data files being archived, generate a searchable content index of associated content attributes relative to the smaller portions of each archive copy, and (c) associate the content index with the respective archive copies; and an executable search filter that is configured to: (i) search in the content index for one or more search criteria received from the user computing device, (ii) cause only smaller portions of respective archive copies that satisfy the one or more search criteria, to be mounted to the user computing device, wherein archive copies and smaller portions thereof that do not satisfy the one or more search criteria are not mounted and remain offline relative to the user computing device, and (iii) present in response to the search criteria a fast-forward progression through the mounted smaller portions of respective archive copies that satisfy the one or more search criteria, without restoring the respective archive copies in their entireties to the user computing device.