I recently discovered the Keep Cup and found it’s unique departure from other reusable mugs refreshing. It was designed by a pair of cafe owners who realized the waste produced by disposable cups. While I don’t find the design outstanding(it looks bloated), it is fun. The cups come in standard sizes to be easily adopted and used by any cafe. The company also introduced customization into the ordering process, allowing you to choose various colors for each part and create your own personalized Keep Cup. While I don’t endorse plastic, the company discusses their considerations thoroughly in their website’s faq.
Design your own Keep Cup.