Anyone brewed beer with natural yeast?

Taking a break from the beer brewing, I just finished up my first batch of natural root beer last night. I cultured my own yeast for about a week prior which I then added to the soda. It was created by putting ginger and sugar in water, then adding a little more ginger and a little more sugar each day. Eventually it got nice and bubbly.

(See the recipe here: http://www.learningherbs.com/root_beer_recipe.html)

But it got me wondering whether or not this yeast would be any good in a beer. Has anyone tried it? Obviously it's unpredictable and likely inconsistent, but it could theoretically produce something interesting. I was thinking of making a one-gallon batch of IPA to give it a try, but thought I'd see first if anyone had tried anything like it before.

spontaneous fermentation, it is risky, but from my experience with beer, done properly the flavors are very nice. I have only done this twice though in a short period of time, I would say I had some luck

There are a few good threads on here about wild yeast/spontaneous fermentation. Look 'em up. Here's one of many: https://www.homebrewtalk.com/f13/ambient-spontaneous-fermentation-43888/

There's an entire section of this forum about this topic- Lambic & Wild Brewing