This talk form Graham Hancock (which has got little to nothing to do with 2012) is excellent, and points out many of the flaws in received wisdom about Egyptian culture, its age, and the use of the Pyramids and the Sphynx. The most popular comment on this video compares Hancock to David Icke, which is a kind of travesty. Icke is, at best, a disinformation agent. Hancock (who may not be right, after all) is a serious scholar.
If you like that talk, then check this series out. It's waaay further out than Hancock (even though Hancock's colleague Robert Bauvall is featured heavily), positing as it does that the Pyramids are actually giant, ancient energy domes. I'm not sure about that, but it makes for some excellent viewing: