Not surprisingly, alot of the earliest tablets and scripts have been shown to be pretty mundane - 24 bushels of wheat, 14 cows, that sort of thing. Basic accounting and contracts.
My husband CT scanned a clay tablet within a clay "envelope" to see if the script inside was legible and decipherable. Just a couple of days before he was to present his paper at a conference in Jerusalem, they were finally able to manipulate the image well enough for a scholar, in California I think, to read it. It was indeed a contract or shopping list of some sort. It was a interesting project for him.