Oh, what could it be?!

I successfully navigated the ~25 miles to work this morning, and was almost parked in the student parking area behind my research building. As I swung into a parking spot, my car started making a delightful scraping noise. Took a look around, and couldn't see anything dragging on the asphalt in accordance with my initial suspicion. I still wasn't particularly worried — on occasion I may have more than my fair share of endorphins, which could keep me from experiencing the proper emotions for a scraping-noise-making car. Actually, I don't have any traumatic car break downs in my background, so maybe I don't know what I'm in for.
I took a looksie (forgive the vernacular — it was introduced to my vocabulary from the book "The Days of My Years" by Earl Smith, some guy who lived in Oregon in the olden days) under the hood and only noticed a cobweb/two and some straw.

Well, not being the Baritone, I don't really know what to think. My rather uneducated hunch is that there's something going on around the right front wheel (that's so vague it could be true!). And the noise occurs at possibly regular intervals when the car is moving, as if it's related to the turning of the wheels.
The Toyota dealer doesn't have time to look at it today, and I really don't want to be stuck in Corvallis overnight... so I think I will have a more extensive look myself.