"The practical applications of quantum encryption may be getting closer. A paper published in Physical Review Letters by Vedran Dunjko, Petros Wallden, and Erika Andersson presents a way to use Quantum Digital Signatures without requiring long term quantum memory.
provides a summary:
Quantum digital signatures (QDSs) allow the sending of messages from one sender to multiple recipients, with the guarantee that messages cannot be forged or tampered with. Additionally, messages cannot be repudiated; if one recipient accepts a message, she is guaranteed that others will accept the same message as well. While messaging with these types of security guarantees are routinely performed in the modern digital world, current technologies only offer security under computational assumptions. QDSs, on the other hand, offer security guaranteed by quantum mechanics. All of the variants of QDSs proposed thus far require long-term, high quality quantum memory, making them unfeasible in the foreseeable future. Here, we present a QDS scheme where no quantum memory is required, which also needs just linear optics. This makes QDSs feasible with current technology."
[Ed. Note] The Physical Review Letters link has all the fun details, but Phys.org provides a more understandable article for the layperson.
There is some name game stuff going on in that the core of the design is rather than storing quantum data directly which is a tough task today, you measure quantum data and stick those measurements in plain old conventional memory till you need them. This is a gross generalization and summary, there's a reason the article is longer than one line...
The name game is you'll still have a box on the flow chart or whatever labeled "quantum memory" its just implemented as "measure and store" rather than directly handling qubits. Maybe you could make a bad analogy to virtual memory handlers.
If you want a stereotypical cruddy soylent-is-automobile-analogy, it would be something like if you can't store spare bodywork panels at the shop because they're a bit unwieldy, just store 3-d models of body panels and print them when necessary. Won't be quite as fast and accurate as picking one up off the shelf, but it'll do well enough.