I think I've seen this kind of set up once a few years ago somewhere, but I can't remember exactly where. If someone knows the original design, please do share, as I wouldn't want to take the credit for designing this. I made some design changes so it fit my need better.
Here is my version of the storage tower.
Step 1: Design and Materials
I have some leftover 2x4, 1/2" plywood and purchased a 4x8 sheet of 3/16" pegboard.
Casters are 4", two fixed and two swivel - that's what I have in hands, and it could be better with all 4 swivel.
Step 2: Making Side Panels
The side panel is 78" x 24", and the pegboard were cut to 75" x 24" so that there was a 1 1/2" space at top and bottom for the top and bottom panel assemblies (2x4 plus 1/2" plywood). Pegboard are screwed onto the frame with 1 1/4" drywall screws. Make sure the screws are away from the center line of the 2x4 so that they don't interference with adjustable shelving holes that will be drilled later on.
The shelving holes can be drilled before this step either by hand or with drill press, but after the final assembly, you still have to drill through the pegboard again.
Step 3: Box Assembly
Use glue and 1 1/4" screws for top and bottom panel assemblies. Then the final box was assembled together with glue, 2" and 3" screws. The structure of the top and bottom panel (plywood and 27" 2x4 glued together) created the stronger lap joint to the side panels with glue and screws, just make sure to pre-drill the holes, and use clamps to ensure the tie rigid connections. Meanwhile, check for squareness by measuring the diagonal.
Then 4 casters were mounted at the bottom.
Step 4: Adjustable Shelving
Set the router fence to 1 3/4" from the center of the cutter, it will ensure the holes would be drilled at the center line of the 2x4. Use one feature on the router, in my situation, was the front end of the fence, as the reference, follow the lay out marks plunge down every two inches. Just make sure you have the same starting point on each side so that the holes are align to each other, otherwise, your shelving will not be level.
The supporting rails are 3/4" x 3/4" x 24" pine strips that I had. Drill two oversize 5/16" holes 1 3/4" from each end of the strip, the oversize holes were to take the dimension variation of the assembly. The rails were then mounted with 1/4" hex bolts, washers and wing nuts onto the inside of the box.
Shelving were cut to 24" x 26 3/8", and they were 1/2" leftover plywood.
Mount all the strips to the box, shelving in place and ready for loading.
Step 5: Applications
I've always struggling about how to use the bench top planer and its out feed arrangement, with the adjustable height of the shelving, it's so much easier to shim the planer to level with my work bench, and use it as out feed, saving space and my back.
Each tower will only take 24" x 30" of floor space, and will also provide additional 2 of the 2' x 6.5' pegboard organizational spaces for the shop. The casters also provide the mobility for them to be move around...
I think the application is unlimited. I will update this when I realize more ideas.