Today HP announced that researchers from HP Labs have proven the existence of what had previously been only theorized as the fourth fundamental circuit element in electrical engineering called Memristor.

Memristor is the fourth fundamental circuit element, along with the resistor, capacitor and inductor, and it has properties that could not be duplicated by any combination of the other three elements.

Memristors could make it possible to develop computer systems that have memories that do not forget, do not need to be booted up, consume far less power and associate information in a manner similar to that of the human brain.
Leon Chua, a distinguished faculty member in the Electrical Engineering and Computer Sciences Department of the University of California at Berkeley, initially theorized about and named the element in an academic paper published 37 years ago.

By providing a mathematical model for the physics of a memristor, HP Labs makes possible for engineers to develop integrated circuit designs that take advantage of its ability to retain information. Now it is possibly to replace DRAM with Memristor technology. The question is how long will that take. HP Labs makes no statement how much time it will take to actually have chips based on Memristors.
Via the HP Labs site.