for those of you who don't know what post rock is exactly, it's not quite experimental, but it is non-traditional rock. unique rythms and sounds are used in post rock. the person who coined the term said this about it: "using rock instrumentation for non-rock purposes, using guitars as facilitators of timbre and textures rather than riffs and power chords." Post rock can range borders from ambient and experimental music to electronica. a few bands that I would consider post rock are: Sigur Ros, God is an Astronaut, From Monument to Masses, Saxon Shore, El Ten Eleven, Caspian, This Will Destroy You, Mogwai. pretty killer line-up if you ask me.
most of the bands that I listed are more structured than slint. It could be because it was made over a decade later, but who knows. it's also less grunge.