Honestly, the notion of encountering a hypo needle never even crossed my mind, but from the posts in this thread, I guess it is a real (or, perhaps, mythical) danger. My neighborhood is similar to Lee's, except that we have an elementary and a middle school nearby and broken glass isn't all that uncommon. I have a sixth sense for dog poop, it seems, having two dogs of my own, and as yet it hasn't been much of an issue.
Before barefoot running, I used to observe landscapes in a broad, non-specific sort of way: "Wow, those hills look like a great place to run." Nowadays, I have a much more micro approach; I'm looking at the running surface and saying things like "Looks like it would really hurt to run on that stuff," or "hmmm...freshly laid asphalt...could be fun..." I couldn't tell chip-and-seal from Chip and Dale two months ago. Now I'm becoming a bit of a concrete connoisseur. Strange things happen in this sport...