One of the things I enjoy the most in songs is interesting and unexpected interludes in the middle of them. This kind of interludes usually doesn't have solos, it's more about the unusual structure of it, the sequence of riffs or variations of themes or melodies. Here are some good examples of that.
Epica - Sancta Terra
I find the small interlude going from 3:17 to 3:57 great and fun. It has a great melody at the begining and then repeting at the end with a little bridge in between. It sounds straight-forward at first but when one tries to count to it, the different time signatures are evident. There are some 3/4 and 2/4 put here and there, here is the structure:
Mastodon - March Of The Fire Ants
I realize that I'm crazy about this type of sections in music with this song. The section going from 2:27 to 4:12 is awesome, it's half in 4/4 and half in 3/4, there are some intersting harmonies between both guitars (something that Mastodon would perfect in the following records). Besides, the song is low, the 6 strings guitars are tuned to A.
Dream Theater - Glass Prison
Of course, I had to put something from Dream Theater. This was one of the first songs with an interlude like this I'm talking about. The section goes from 11:10 to 12:49. It's a frantic, non-lineal insane sequence of interwined riffs, it's tripping!
