Because I do leather work, I am always interested in new or unusual designs. I saw a neat design for speed loader holders, but don't know who made it.
It carried one speed loader with bullets facing down, and one with the bullets facing upward. You belt goes through the MIDDLE of the holder, and 3 rounds of the speed loader go inside your belt, and 3 rounds go on the outside of your belt. That way, it only takes up the room of one speed loader on your belt, but actually holds two speed loaders.
My former partner at work used to have one and I thought it was a really slick design. He bought it at a gun show in Portland, OR from a fellow who did custom leather work. It was similar to the Safariland split six speed loader holder, but it held one speed loader on top, and one on bottom of the belt.