I was expecting a drove of insults and a long speech from someone about how this forum is to share information and such.
But since you guys are so unbelievably nice, I can't resist but give away the "secret". After all, you can't abandon you friends, can you.
So, the key word in this technique is "bark stripping".
I am not going to do any drawing here, use your imagination. But the essence of it is that you take a young juniper (but not too young, the lower trunk should be about half an inch thick), and remove a wide strip of bark from the nebari and upwards (about 50% of the bark). You do this in an irregular corkscrew fashion, like an upward spiral. It has to look natural, so the coil that you create is at some place looser, at other places tighter. You don't want to make it like a candy-cane, but more natural.
What happens is that from the time you removed the strip of live bark, the trunk will start growing only along the live vein. As the vein thickens, the whole trunk will take on the shape of those coils that you see on those marvellous shohin and mame junipers in the Japanese catalogues.
In addition to this technique, you also wire the trunk, adding additional curves to it. But you do the wiring at the beginning, and strip the bark later, when the trunk has somewhat thickened already. You don't want to do the bark-stripping on very thin trunks and branches, they need to have some volume to work on.
I became aware of this technique about 6 months ago, after watching Linsey Farr's video series on the Internet. In one of the episodes (don't remember which one), a professional Japanese shohin bonsai grower was showing his little junipers, and kept mentioning over and over the technique of bark-stripping on the lower trunk of his junipers. I don't remember that he described the technique in detail, but that's when the lightbulb came on in my head. I've been playing with this idea for a long time, and I remember talking to Mas Ishii about his little contorted junipers, but he never really gave away his technique. Lindsey's video helped me to figure it out.
I have about 15 little shimpaku stock in my possession right now, so this winter I will apply this on all of them. Then they will all go back into the ground for 4 years worth of thickening.
There you have it,
I just gave away something that could have made my fortune. You guys can start sending me your checks at your earliest convenience.