In my opinion, if you aren't brewing coffee at home, Starbucks is the best deal for coffee on the road.
If you're a gold card member, you get free flavor shots and free refills. Plus, each drink qualifies towards a free beverage in the future.
If you compare prices for brewed coffee, it's the cheapest I can find.
So, order a tall brewed coffee with a shot of your favorite flavor, add your own adjustments and enjoy a fancy frugal coffee in the restaurant. Then, get a free refill for the road!
15 (?) of those later you get a coupon in the mail for a free drink. You also get one on your birthday. That's when you order your $6 Venti Fancy-Drink-Special!
No, it's not as good as brewed coffee in a Thermos from home, but it's a good deal for when you need a place to meet a friend and the friend likes coffee shops.