I just came across some news articles about this Italian musician/computer technician who has claimed to have found written music hidden in Leonardo's Last Supper painting. Here is a link to one of the articles that has a diagram:
The articles don't go too in-depth so I don't know what to make of them. But something in one of the articles bugged me:
"The result is a 40-second "hymn to God" that Pala said sounds best on a pipe organ, the instrument most commonly used in Leonardo's time for spiritual music. A short segment taken from a CD of the piece contained a Bach-like passage played on the organ. The tempo was almost painfully slow but musical."
A Bach-like passage? During the Renaissance? Of course, they said it was a short segment from a CD of the piece, but why do they mention that, then, unless it was supposed to be directly related? People, please.