From today Starbucks are offering a $1 plastic reusable cup in all of their US and Canadian stores. This cup will pay for it self in 10 visits to Starbucks as coffee bought with your reusable cup is 10 cents cheaper. Starbucks already offers this price reduction when customers bring in their Starbucks tumblers (and in the UK too), however it is hoped that the cheaper reusable cup will encourage more customers to change their habits and reuse their cup.
Starbucks will wash out the reused cups with boiling water free of charge before filling it with your chosen beverage. It is encouraging that large corporations are increasingly trying to change the culture of throwing away paper cups.