Really? There's a thread of over 800 comments on it already. I think most things able to be realized have been realized. My favorite realization: no bathrooms.
FWIW Hyperloop doesn't bring much to the table, even if it would work (in principle, yes, in practice, many years and billions to iron out the kinks), there are many better options.
Further, the biggest question is QUI BONO?
Rich people who want to shave an hour off their inter-dealing travel time. Much better to spend the money on, say, automated busses, to shave 30 minutes off the commute times for the many.