I have been piecing my gear together, mainly due to a friend upgrading.  I have an EI carrier.  I am looking for some method to carry a second optic.  I have two LaRue mounts, one with a DMS-1 in it and another with a fixed 10x mil-dot.  I would like some sort of method to carry which ever one is not mounted on the gun, and have it fairly easy to access.  Does anyone have any suggestions?  

I'm not sure if I want something that I could attach to my armor, something to go around behind a thigh on a belt, or something to put it in my pack with.  

taggage, cause i'm interested in this one too.

this may or may not help

Aimpoint Magnifier Pouch - M4Carbine.net Forums

http://m4carbine.net/showthread.php?t=20277

full size optic as a spare? Needs to go in your pack. I keep my 3x magnifier for my aimpoint in a ute on my armor

That thread hasn't really developed yet, but I'll watch it.  I imagine the ACOG and Aimpoint pouches are too small.  I have eyed a couple of the MP5/UZI mag pouches.  I'm not sure if theyd handle the diameter though.

Quoted: full size optic as a spare? Needs to go in your pack. I keep my 3x magnifier for my aimpoint in a ute on my armor

It is not a spare optic.  I guess realistically if Id ever need the 10x Id have time to set up.  I may just find a nice case for it and go that route.

You should look at some of the padded zippered pouches that Outdoor Research makes.  I have a green one, that fits a 3x9 power.