Great use of space! I really like the 'repurposed' desk, although I think I'd be a bit leery of putting it on stilts like that.

Your space if far more organized and neater than mine - good for you! My problem with organization is that I'm really good at taking things out, but not so good at putting them back!

Sandygirl, I don't have your problem and the amount of slant you have is not completely clear, but have you considered hanging your shelves down from the slant ceiling on chains, or for fabric storage, you could hang metal clothes rods from chains, maybe even two rungs long, and use regular hangers or pants hangers to hang fabric pieces, rolls of batting etc. I don't think I would do it the entire room or it may end up feeling like a bowling alley (unless your room is quite wide).

I would first place the desk and chair so I can walk in, sit and stand up again without hitting my head (done that too many times in my craft/storage room). A book shelf for stash/book can be placed up against the back of the desk or covered with a curtain if you don't want to look at it. If it's tall you could use that vertical space to your advantage. There's an odd space just inside the door my DH put up pegboard and hooks for me to hang rulers, etc. on and I put the mats underneath. Might have to take pictures and let you see my mess tomorrow.

Slanted ceilings/walls
 

This is my storage area for not only my quilting but other items too. It is unfinished (and will stay that way for a while as I am unwilling to move things out and move them back in by myself again). The area adjoins a gable-style addition to the roof portion of the original house. There are two roofs sloping down and in and two down and out. I think you can see the beam I have to watch my head on, and how my DH used it and studs for the pegboard so I can hang rulers, etc. My fabric cabinet is back to back with another one and the sloped wall holds batting. Hope this helps you find your creative side.

I bought this floor lamp at Lowe's that works great in my slanted sewing room! Plus I can turn it around & shine the light on my cutting table. We were going to go with track lighting, but this is better for now.

I have slanted ceilings as well. I too am looking for a better way to store and organize, lots of good ideas on this posting!
I have a stairwell that comes up right in the middle of the room making it even more difficult to use. So far all I do is store totes in the room but I want to get a sewing table and cutting area in the room also. Challenging to say the least !