  The concept of an all pervading Aether is age old, and contrary to popular
belief, it survived the twentieth century too though with different nuances.
Using this concept of a background Quantum Vacuum, the author in 1997 proposed
a cosmological model with some resemblance to the Dirac cosmology, which
correctly predicted a dark energy driven accelerating universer with a small
cosmological constant, as was subsequently confirmed by observation in 1998.
Moreover the so called Large Number coincidences including the mysterious
Weinberg formula are deduced in this theory, rather than being ad hoc. We
examine the concept of Aether in this context and indicate how this dark energy
may be harnessed.
