My buddy's beer tap faucet always had this creeping mold on it. Also some of us figured out that big chunks of stuff would occasionally come flying out into our beer as it was poured.

One day I had the presence of mind to violate the usual protocol of swallowing with as little chewing as possible, and actually picked out and photographed the resultant chunks. Much to my dismay, it was a fully formed mushroom shaped critter with stalk and head and everything. It was mostly bluish green but had concentric rings of beige to brown also.