I fooled around with sourdough a few times. My first was a starter I collected just by sitting flour water and sugar out on the back deck on a windy day. After all, natural yeasts are EVERYWHERE.
I recently ran across a guy that makes blended videos of woodworking and cooking. The first video I saw was him simmering wood chips in cream and sugar, then making a wood flavor infused ice cream. He then turns a bowl from the same wood and carves a matching spoon to eat the ice cream. I followed his videos and ran across one where he made a sourdough starter from juniper berries he had collected. Juniper berries have a dusty bloom on them that is pure yeast. I did a little research and found that the ground hugging juniper in the Black Hills is indeed Juniperus communalis, the same juniper that grows the berries used in cooking and making gin! I picked a mess of berries last fall on a ruffed grouse hunt and I intend to crush them and use them as the base of a new sourdough starter soon.
I don't tend to stick with sourdough starters long because they are a lot of work and I discard a lot of starter for what little baking I do. Still, It's fun to brew up a batch of bread from the wilds now and then.