I can still remember my first semester of college when I realized I had done the unthinkable - forgotten to put on deodorant. I dashed to the local college shop, because I just couldn't go without it all day. I bought some weird baby powder smelling roll on that I would never use again. It only set me back $4??! It was a lesson learned.
I now am prepared for those everyday little disasters and touchups. Travel size deodorant (you have to buy roll on if you leave this in your car, trust me!), travel toothbrush, flossers, body spray, etc are stocked in my car and purse. Keep your eye out for your favorite products in travel size which is pretty easy to find with the 3 oz carry-on regulations. You will not only prepared, you will save from buying some overpriced product you will probably never use again.