This was pretty simple and elegant (and inexpensive and easy to make). It's a piece of aluminum and two screws. I'll probably do something like this.

Here's another variation on the same theme. Still two screws and aluminum (I think) but this time there's a fancier shape and a lot more polish.

And yet another variation on the same theme. I'm guessing this one was done out of fiberglass but I'm not sure. Still just two screws.

Any bets on what this guy does for a living? I'm guessing he's an orthodontist. This cowl pin retainer has 4 screws (as I recall 2 more are on the inside) and it appeared to be painted aluminum. The retaininer wraps around the edge of the air inlet. It really looked nice, I'm sure it works great but it seemed like more work than I'm inclined to give to this task.

This was a clever idea, imo. The builder brought the cowl pins out to the rear of the cowling in the NACA fresh air inlet and then simply bent the pin at a right angle and had a hole to insert the bent end of the pin into. Simple, cheap and effective. Unfortunately it looked like the paint was taking a beating from either use or vibration in flight. I'm guessing there's a solution besides a polished aluminum plane (or a canope cover).

Here's another clever idea. It involves one screw and a retainer clip similar to what's used in the fuel tank to support the fuel vent line as it passes by the fuel cap. I like form to follow function and I'd give this idea an A+ for elegance in this respect...unfortunately, the idea looks very unattractive to me so I won't be using it.

Here's the same idea executed with a lot of style. It's simple, effective, and meets my definition of functionally elegant.

Did you notice, no one found it necessary to use nine screws to hold the cowl pins in?