Which soil innoculants are folks using?

I watched Geoff Lawton's video on soil and was amazed at just how much life is actually in the soil. I also came across some information on inoculating soils to speed up the soil life formation process in new hugulkulture beds. Which inoculants have folks had the best luck with?

I've never used any commercial innuculants, but I have spread a bit of soil from under a friend's really productive apple tree around my young trees.
Totally unscientific, with no controls, comparisons etc!
The trees are healthy though