Tonight I gave a minor invention(?) of mine to my kids' Tae Kwon Do instructor. It addresses a problem that I saw.
Prior to every Tae Kwon Do class, which takes place in the school gym, the instructor has hang up the class banner, which is used during their opening and closing ritual. However, it's an awkward process: the instructor has to lay the cord across the top of each of the blue padded things (which keeps kids from bashing into the vertical I-beams), then run the cords down to the stacked chairs and awkwardly tie the cords to the chair legs.
Not only is it awkward, but there are two other disadvantages: he would prefer to use the other side of the gym -- but the chairs aren't stacked over there, so there's nothing to tie the banner to; and the cords are unsightly when they're running down at an angle.
The above is a snapshot of what the banner looks like with my little invention. When I set it up, the whole thing took me about two minutes; no knots were needed; and the tails of the cords were hidden.
Here's a shot of my device. Basically, they're just wooden hooks with some tie-off cleats on the front, some white felt on the insides (to prevent the paint on the I-beams from getting scuffed), and an additional hook on the back.
Here's another shot, but at a bit of an angle.
To me, this looks a lot like something my late (paternal) grandfather would've cooked up.
Here's a shot of the left-hand hook, in action. Notice how I've lashed the cord to the cleat, then brought it around back and hooked it over the rear hook. This keeps the rest of the cord out of the way, and also maintains tension on the cleat.
Here's a shot from a different angle, where you can see the cord hanging down the side of the blue padding.
Finally, here's what the tail end of the cord would look like without the hook in the back: it would flop forwards, which would look ugly and also allow the cord to unwind from the cleat.
As usual, this was all done with hand tools: a trysquare, handplane, some chisels, a backsaw, a bradawl (for making the location of the holes). The exception was a power drill, for drilling the screw holes.
Pathetically, this project took me about two months to complete. However, part of the delay was gluing the felt (I had to do it in stages, allowing about a day's drying time between stages), and the Danish oil also took a few days (due to drying time between coats). Plus, I only worked on it during weekends -- and only a little bit each weekend.
But part of the delay was just spending time on other tasks.