Relax people, this is massage for your brain-cells. In fact, if it wasn't for the revolutionary guitar-solo (which you will hear in this song), it would probably not be so special at all.
The album - with the same name as the song - was released 1971 and also ranked #486 on Rolling Stones magazine's list of "the 500 greatest albums of all time".

http://en.wikipedia.org/wiki/Maggot_Brain

This is the original recording of the song, which means the song is over 10 minutes long(!), but do not fear, this is something very exotic for it's time... (less info)