Once (a couple of decades ago) I was on a training ride in a rural area, and I caught up with a small truck at a stop sign. I started drafting it, and just cruised along at a steady 30 or 35. Hmm, thought I, ... smells like something died... the smell is not going away... oh, geez, this truck is driving around picking up dead animals for the rendering plant! (It's dynodonn's tallow truck!)

Perfect for drafting, but I let it go.