Oh yeah, I am looking at possibly culturing up some of the Berlinerweisse yeast. The label says it is bottled with "five proprietary yeast strains." I haven't even tried the beer yet, though. My wife says it isn't all that sour and that she likes my Berliner better.
Either way, proprietary yeast makes me interested in trying to use it in a homebrew. I only have two bottles left though, so it may take a few steps to get close to a homebrew sized pitch. And there's no telling what the balance between the 5 yeasts might end up being.
I'm guessing there is some lacto and maybe some wild, Wisconsin-native yeast in there. Could be cool.