I'm pretty passionate about Tool's music, hehe. Plus it gave me an excuse to try out the fancy new table function. I actually calculated the time for Lateralus counting Eon as filler, just in case. I mean, it's not necessary, but I love the way it transitions into The Patient. For me I guess there's fillers and then there's segues. Ænima has more filler than segues, while Lateralus has little to no filler (apart from Faaip), and 10,000 Days has tracks that double as filler and segues.
Ænima - The only two I'd count as segues on this one are Useful Idiot and Intermission. Maybe it's because of how much I've listened to the album, but I quite like how H. and Forty Six & 2 are joined by Useful Idiot. Intermission is just neat and when actually listened to, it is a nice set up for the melody of Jimmy. Message, Die Eier, Cesarro, and Ions are all basically worthless in terms of value to the album. Die Eier is neat in a novelty sort of way, but it's along the lines of what they typically put at the end of the album. I think it's out of place in the middle and it should probably be after Third Eye. I really like this album, but it doesn't seem to be as cohesive to me as Lateralus.
Lateralus - I'm particularly partial to this album because it helped me out of an extended period of depression. I won't go into that now, but the only thing I'd really call filler on here is Mantra. Well, Faaip is too, but I tend to think of their closing tracks in a different light than their typical filler or segue. I think this is a really great album because all of the songs deal with personal growth, in one way or another. In that way, it has more of a theme than the other albums. Well, maybe not Undertow, but I was never all that fond of Undertow. I mean, I like it, but I don't listen to it nearly as much as the following three.
10,000 Days - As with Lateralus, there's not much here I would really call filler. The first track that could be called that is Lipan, but I don't think that's very fair. I think it creates a good atmosphere to lead into Lost Keys. With the droning in the background of Lost Keys, I can see people calling this filler, but I think it is a good segue between Lipan and Rosetta. The Lipan Apache are desert dwelling natives, and the chant in Conjuring seems like something that would occur in a ceremony laced with psychadelics. Then Rosetta tells the tale of a drugged out UFO chaser encountering aliens. I think Lost Keys fits nicely in the middle, explaining what happened after Rosetta. Other than that, I can't see what else could be considered filler except Viginti, but I explained my feelings toward Tool's ending tracks.