Plausible Ancient Inventions of Egypt

I can be sure that this isn’t my idea, originally. Surely Archeologists have considered this by now. My reason for floating this is that the idea is not completely unreasonable.
Even by modern day construction standards, the ancient pyramids of Egypt would be a gigantic building effort. It is estimated that the Great Pyramid of Giza weighs 6 million tonnes. Using conservative estimates, that translates into 800 tonnes of stone being needed to move each day, over a construction period of 20 years. 800 tonnes is plenty of mass, greater than the fully loaded weight of an Antonov An-225 cargo jet. It is still a readily movable mass even by the standards of the 1800’s steam engines. Now it is already known that the Greeks used the Aeolipile, which was basically a steam powered rocket engine good for operating small devices. Now scale up the machine or a similar machine and you have a device that could move a stone weighing many tonnes. It is already known that the Egyptians had at least a rudimentary understanding of smelting and molding iron. What if they did have the ability to manufacture an entry-level steam powered crane? Where is it? Assuming that I’m right, it might still exist somewhere buried under desert stands. Perhaps it was sandblasted out of existence thousands of years ago by the desert wind. Maybe it was long ago dismantled. In any case it isn’t unreasonable for technology of that class to be destroyed by nature in a century or two.
The ancients were far smarter than we give them credit for, they might not have had microchips; but they still had recognizable contempory technology. They did invent an early battery. This isn’t entirely impossible.

Universal Matter

You know those scary movies where machines transform from one shape into another, moments before they kill you. By now you should not be surprised to know, the pentagon is already building these monsters in their effort to kill you someday.
They already have a name for it, programmable matter. This programmable matter is or will be miniature machines, very likely with its own central processor, locomotive, memory, and communication system. The rest of the operation is only a matter of method. These projects are funded under the Pentagon’s DARPA program, which is currently five months into its second phase. Their hope is that by next spring, they could build a few primitive programmable objects.
Imagine it! Someday you could drive around town in a muscle car and at the mere hint of a storm, instantly transform it into a sports utility vehicle. The Pentagon wants it for other reasons. You have a villain held up in a bunker, why risk your life trying to seize it. Pour a cup of mercury like nano machines at the entrance, and they will find their way in and have a party with the occupants.
One team from Harvard University is pursuing a strategy of a generalized Rubik’s Cube; that can fold into all sorts of shapes. The team from M.I.T is trying self-organizing origami. Needless to say, this engineering is proving to be very mathematically challenging.
My advice to them, many new technologies fail simply due to engineers failing to account for everything. While this can never be eliminated, you can build your machines to be as simple as possible.