Having personally spent a good deal of time worrying about my dog and wondering what yelps of pain really mean – is she in pain all the time? just when she yelps? how much pain? does it just startle her or is is excruciating? – I know I would pay a significant amount of money to answer the question "how much pain is my dog in?" Well, now, thanks to an Ohio nurse, I can find out. She’s developed a $600, palm sized device that measures stress, a good indicator of pain level. She’s selling them to vets, but I bet wealthy individuals would be willing to buy them, and I bet a whole bunch of us would be willing to rent them when trying to diagnose chronic health problems in our pets.