So what am I to do? The Mini-Me has grown on me to the point that eviction is off the table, but I cannot give up my sheltery, cavernous mistress, the Garage, so it's time to get creative.
I can get my car into the garage if I line up all the toddler toys along the wall, but then opening my car door is difficult, and walking between the car and the wall gets hazardous. So these things are going to have to find their way up on the wall. I brainstormed up a system using french cleats to make it adjustable, with long extenders so that I could hang the cleats up high on the wall to keep them out of the way.
-Plywood (at least 1/2" thickness)
-Wood to rip into long extenders (I used 1"x12" pine)
Step 1: Rip Your Cleats
I used 3/4" birch ply to make my cleats because it seemed pretty burly and didn't break the bank. Set your table saw blade to 45° and rip however many cleats you think you'll need from your plywood. You can probably be less wasteful with your wood if you cut strips into little parallelograms like in the picture; I started out ripping several wide strips with the blade at 90° and then ripping those in half with the blade at 45° to make the cleats. I realized towards the end that making all my cuts at 45° would definitely save some wood and probably wouldn't weaken my cleats at all. Remember to leave at least one strip that you will use to make the reverse cleat (that attaches to the hanging piece and fits into the cleat on the wall).
How wide should you make your cleats? Good question. I have no clue as to how much the width (or height, once the cleat is hanging on the wall) affects the strength, but I felt pretty safe with 1.5" or so of wood flush to the wall.
Step 2: Mount Cleats on the Wall
Once you have everything positioned to your liking, mount the cleat to the wall. I went ahead and used big 3" decking screws for this, just to be sure of their strength. It's also a very good idea to use partially threaded screws, which will grab the stud and pull the cleat to the wall; you'll likely be on a ladder and it's nice not to have to worry about pressing the cleat against the wall with one hand while driving with the other.
Step 3: Make Your Hangers
Once you have your hangers cut to size, cut cleats of the same width from one of your leftover cleat strips you ripped earlier. Glue and clamp the cleat, making sure that the direction of the cleat is down and away from the top of the hanger. Once the glue is dry, drill pilot holes and countersink them, then drive in a couple of screws for added strength.
Also glue on a spacer block on the bottom of the hanger, on the same side as your cleat. This can just be glued and doesn't need any screws; it's just a spacer and I can't imagine it encountering any crazy tensile or shearing forces.
Attach a mounting block wherever you intend to add a hook. This piece of wood WILL experience a good bit of force, so I recommend using plywood scrap for this instead of solid wood in order to reduce splitting (I prooomise I used plywood scraps for most of these, but the one in the picture has white pine. Do as I say, not as I do). Also drill pilot holes and add a couple of screws to the mounting block unless you have a lot more faith in TiteBond than I.
Drill a hole in the mounting block that is sized appropriately for your hook. I experimented with a lot of different hook types and placements, and will probably find a use for all of them. You can also add multiple hooks (on multiple mounting blocks) to the same hanger. This system is extremely versatile and customizable.
*UPDATE: I've posted a separate instructable with an alternate "hoist" design for the hangers here.