Apparently Tool included a hidden track on the album, but it's not tacked on at the end of the album like it's usually done by most bands. In fact, the hidden track is revealed by actually combining/mixing 3 songs. on the album together. One of the tracks is 11:14 in length, while the other are 6:11 and 5:03, giving a total of 11:14 as well! Some genius figured out that it wasn't pure coincidence and put them together (details on how to do it here)
So anyway I tried it myself and the results were simply amazing. The tracks sync incredibly well, way better than I thought they would, but the most surprising thing was that the end of two of the tracks were almost identical (including the vocals!!), leading me to believe that this was authentic and not just some fan-made delusion.
Anyway it's pretty amazing stuff, it's hard not to marvel at their creativity.