Bill, you're a genius! I have eyed that big wide space between the camper and our bedrails for years thinking I could use the space somehow. Extra gas tank? Fresh water tank? Grey water tank! Excellent. A new project going on the list. 
Ted made the point above here. Bill had one good answer, but I don't think I want a gray water tank.
And yet, I have quite a bit of empty space between camper-outside and truck-bed-inside, too, and in a truck-camper combo in which space is at a premium, it seems a waste to let space go to waste...
I didn't want to hijack that thread to discuss other options, so I'm starting this new topic.
How (if?) have others made use of their camper/truck-bed-wall inter-space?
I know that ideas/answers will be different depending on model of truck and model of camper; some combos have a lot more/less space than others and whether or not the space is accessible from the rear varies, etc.
Seems like I've heard of people using it for storage -- accessible from the turnbuckle-access panels on the inside...for example. Some kind of storage that doesn't result in stuff sliding around and getting out of reach.
What other ideas?
Ted made the point above here. Bill had one good answer, but I don't think I want a gray water tank.
And yet, I have quite a bit of empty space between camper-outside and truck-bed-inside, too, and in a truck-camper combo in which space is at a premium, it seems a waste to let space go to waste...

I didn't want to hijack that thread to discuss other options, so I'm starting this new topic.
How (if?) have others made use of their camper/truck-bed-wall inter-space?
I know that ideas/answers will be different depending on model of truck and model of camper; some combos have a lot more/less space than others and whether or not the space is accessible from the rear varies, etc.
Seems like I've heard of people using it for storage -- accessible from the turnbuckle-access panels on the inside...for example. Some kind of storage that doesn't result in stuff sliding around and getting out of reach.

What other ideas?