Generally, I never found fanny packs to be very comfortable. I'd expect to either loop it over my shoulder or have it attached to another pack.

Here's an interesting solution to the Nalgine problem:
http://www.supplycaptain.com/store/index.cfm?fuseaction=product.display&Product_ID=309
If you don't mind digital camo...

And:
http://triadtactical.com/tab1/store/category/9qqr/Pockets.html%253Fcategory_id%253D9qqr

And more here:
http://www.texastacticalgear.com/index.p...5d619c007b301b6