|Twilight (top) and Dawn (above) KeepCups. You can also design your own cup...|
If you're a coffee-shop frequenter who enjoys more than just drip coffee, you need to get a KeepCup. These are the "first barista-standard reusable cup," because baristas can make perfect to-go coffee drinks in them. (We can personally attest to this!) Their website says, "When your coffee is made in a KeepCup the crema on the shot is not broken and the portioning of milk to coffee will be correct." KeepCups are plastic, yes, but they are BPA-free and non-toxic—and having one cup you reuse all the time is far better than blowing through the disposable cups at most coffee shops. (Be sure to read the fantastic Sustainability page on their website if you're having any doubts, or if you're simply interested in the environmental impact of all those coffee cups we use.)
Just for fun—you can also design your own cup!