The Starbucks chain is commemorating Earth Day nationwide today by giving away free coffee, as long as you have a reusable mug. Bring it in to a participating outlet (we assume most of them are participating), get it filled, and be on your overly-caffeinated way.
Full disclosure: Patch.com and Starbucks have a marketing deal where links to your local Patch site will pop up once you log on to the Internet via the coffee chain's free wifi. That said ... FREE COFFEE!