Zero Point Energy

A reader writes:

What about the Quantum vacuum, which isn’t a vacuum at all. Zero Point energy is available now.

To which I respond:

I’m very interestested in this, but most people tell me it’s poppycock.  (I.e., zero point energy is real, of course, but the idea that it’s available for use is poppycock.) Can you point me to a website that presents this in a clear and compelling way? 

It’s true that a particle at absolute zero still has some energy, due to the Heisenberg Uncertainly Principle.  I.e., if a particle had no momentum, we’d know exactly where it was, which is impossible.  However, is there any possible application of that in terms of harnessing useful work?  Most people, and I’ve spoken with a heck of a lot of extremely senior and fair-minded people, say no.

I post this to stimulate conversation on the subject; I hope readers will please feel free to add clarification.