So several days ago, I was Moccing, and I needed a black 1x2 slope. Common mold, common colour, should be a common piece, right? Well, apparently in this case common mold + common color = extremely rare piece. It took me hours to even locate one.
Flash forward to a few days later, Moccing again. As I'm doing so, I launch into a discussion about my earlier difficulty with finding a black 1x2 slope. As I'm talking, I'm digging through my tub of black parts, looking for some piece... and I find a black 1x2 slope, right there.