Something like this crops up every now and again - secret passages, a mysterious grille, possible air vents etc. etc. Now it's the discovery of 'voids' in the pyramid of Cheops.
http://www.bbc.co.uk/news/science-environment-41845445

We wll probably never find out their purpose as they are buried too deeply in the structure, but no doubt fun will be had in considering all the possibilities.

I had read they were probably internal collapses as purpose-built voids beneath them gave way in antiquity. At least that was the working theory the same guys started out with who are now giving out press releases about their most recent data (which actually doesn't seem to contradict their original ideas at all).

Ben Carson will of course declare this as proof that they are grain silos built by the lad with the amazing technicolor dreamcoat. Carson, obviously due to his extensive construction knowledge, is currently the US's Trump-appointed United States Secretary of Housing and Urban Development. And not a dreamcoat in sight.

On the radio this evening, and I didn't catch all of it, but someone was saying that voids would be essential to lessen the load on the structure. Solid stone would cause too much compression but voids here and there would act to lighten the load. Makes sense to me.

Yes I thought that was likely too. Egyptian building technology used only lintels or corbels to brigde spaces and didn't include weight-bearing structures such as arches. Accordingly they appear to have deliberately constructed empty chambers above vaults to reduce the weight on the lintel and so stop it collapsing. I think it's been shown that this was the function of the several inaccessible voids directly above the so-called King's Chamber. As these chambers were not intended to be seen, they were not finished in any way and so retain their rough-cut aspect. This new void, or voids, which appears to lie directly above the Grand Gallery and be of much the same dimensions and orientation, was probably constructed for the same reason. If so it would be unlikely to contain very much, although of course it might still have interesting masons' marks, graffiti, discarded tools etc. ... although it would be nice if it was stuffed with books.

Wouldn't it indeed!

I assume it's feasible these days to access them with a camera? There was a previous much-hyped attempt (I think by a Japanese team?) to do a similar exercise with the long shafts incorporated into the build but which turned out to be rather an anti-climax in the end - debris prevented them from getting very far into the voids and that which was visible was remarkably unremarkable, alas.