Don't tell Zahi Hawass (long time [and now former] Egyptian Minister of Antiquities) this, but there's a lot of evidence to suggest that many of the stones that the pyramids were actually made of a sort of proto-concrete rather than carved from large limestone quarries. This isn't a new theory either, about 2,000 years ago a Roman Navy commander wrote:

In this way occurs a multitude of heaps (of minerals) which can be transformed into real rocks. They Egyptians make vases in this way...

Romans themselves also had concrete, so it isn't far fetched to suggest this scenario. Consider for a moment that, as the article states:

Other scientists, however, are using modern techniques to examine the stones. In the 2011 paper, Were the casing stones of Senefru's Bent Pyramid in Dahshour cast or carved? Multinuclear NMR evidence, nuclear magnetic resonance experiments show the casing stones of Senefru's Bent Pyramid to be a combination of limestone grains from one quarry cemented with a calcium-silicate gel from a second quarry.

Interesting thought and definitely far more efficient than the current theories on how huge stones were lugged up the Nile and across the desert.