Maybe the final operational post on this episode in USMC history. I cite a WaPo article on the logistics of exiting. Here is one thing left behind (as did the UK):
The Marines decided to leave 420,000 bottles of water, which if lined up end to end would stretch for more than 50 miles.
Link:http://www.washingtonpost.com/world/...d5_story.html?

I do wonder if anything was moved overland to Karachi (which is subject of a thread on OEF logistics).