Thought I'd share this with you, since I noticed this a while ago yet haven't found anything about it on the internet, despite there being several cool articles about the many nuggets/references within Octavarium.
The reference is the release date of the album (and, of course, the song): 7 June. June being the 6th month of the year, this is the 7th of the 6th, or 6/7. Given that one of the central themes of Octavarium are the numbers 5 and 8, and the numbers between 5 and 8 are (obviously) 6 and 7, this could be another reference as to how we are "trapped inside this Octavarium", so to speak.
I don't know whether this is entirely coincidental or just another reference in Octavarium that has gone unnoticed, but I thought it was really cool so I decided to share it with you.