Tipping Your Barista

I got a kick out of this video that a co-worker shared with me. I think most baristas can relate-- I can't help but look out of the corner of my eye as I wait to see how much a customer will tip. How much do you tip your barista? Does it depend on the service? Do you make it a point to always tip? Or never tip? I have heard some people say that they don't know what a reasonable tip is for a barista compared to a tip for a waitress where 8-10% is somewhat standard. In my experience, most people who tip at all will tip a dollar. Fifty cents is reasonable-- anything less than 10 cents however, is a bit of a slap in the face. If you want to be safe, tip a dollar and your barista will be very thankful. What are your thoughts on tipping at the coffee shop?