Temporal links allow recordings of multi-user sessions to be dynamically inserted into current virtual worlds in a flexible and principled way. This paper explores key applications of temporal links, showing how they can add new content to virtual worlds, support usability and system evaluation, and link VR to other media such as film and television. These applications illustrate just some of the possibilities of a ubiquitous and flexible record and replay facility such as temporal links. Building on our experience of implementing temporal links in the MASSIVE-3 system, we identify key requirements for system architectures that wish to support an equivalent mechanism.