I brewed a Berlinerweiss with a friend where we crushed a pound of grain and let the natural bacteria create a disgusting smelling mess of lactobacillus. We did a short boil for a small hop addition. Inoculated with the lacto and let it go, then tossed yeast in.
It had a real nice tart character and I was chugging my half.
Not quite going straight from mash to fermenter, but close with good results.