Superfluids can, in theory, be used in topological quantum computing .
Superconductors are materials which offer effectively zero resistance to current at nearly absolute zero temperatures. They have been in the news recently in the form of superconducting magnets for the Large Hadron Collider.
Superfluids exhibit fluid dynamics analogous to the electrical dynamics of superconductors: they will flow through the finest capillaries without friction. The connection between superfluids and superconductors is more than an analogy: the quantum theories of the two phenomena are intimately related.
Prof. Sir Anthony (he was knighted in 2004) spoke with me by phone from his office.
Prof. Anthony J. Leggett of the University of Illinois at Urbana-Champaign shared the 2003 Nobel Prize in Physics "for pioneering contributions to the theory of superconductors and superfluids".