One small way to go green is to return to an older style of grocery shopping—before the first supermarket opened, grocery stores were full-service affairs, where you'd walk in and hand your list to a salesperson, who would run up and down packed aisles to retrieve your items from a list. Nothing was branded or in colorful packages; if you wanted flour, sugar, or spice, the quantity you wanted would be scooped to order and put in a small bag. We thought of this when we visited the Spice House in Evanston, Illinois...
Now, you're not walking to a counter at The Spice House, but rather, browsing through the store, and it is a delight for the senses. (It's still a bit old fashioned—someone else does do the scooping for you.) Buying from bulk, which is not to be confused with buying in bulk, makes sense. It may not seem like much to cut out the little glass jar that holds your spices, but think about the global impact of millions of small, relatively heavy glass jars used to transport minuscule amounts of spice. Or look in your kitchen cabinet and multiply that many spice jars by how many households there are in the US, and then imagine driving them all around. It's a small improvement, and not one that will save the world on its own, true, but it comes with other benefits.
Shopping for food this way—think peaches from the Farmer's Market instead of the plastic-encased four-pack at Trader Joe's—makes the shopping trip a much richer experience for all the senses, rather than the purely visual bombardment of a modern grocery store.
The Spice House has locations in Evanston and Chicago, Illinois, and Milwaukee, Wisconsin. In Berkeley a similar store, though not as pleasant of a shopping experience, is the Country Cheese Coffee Market. Is there a similar store in your neck of the woods? Let us know below.

Sheex Bedding
In Berkeley, I love love love going to Lhasa Karnak! Most of their spices are about $1.00/oz, which is WAY cheaper than what you find at a grocery store. Not to mention a much wider variety of spices, and generally much fresher!
Another decent option is to pop into a Penzeys store. Penzeys is the spice of choice of many chefs (Rachel Ray uses them on occasion in her shows), and their stores are fantastic. When you go to their stores, for most spices they allow you to buy a plastic baggie of their spices for much cheaper than they sell them in the jars. Closest one to Boston is in Arlington on Mass Ave.
Oh, there's also Christinas on Cambridge St in Cambridge, right next to the ice cream place, too...
I go to http://www.thespicehut.com/ up in Bellingham, WA. There is also Market Spice in Pike Place Market. Either one is amazing, with a similar experience. I recommend them both, if you get over this way.
I lived in Colorado Springs and could buy bulk spices from Whole Foods. They may not have the selection that the ones above have but they are easier to find. We bought all our spices, flour, sugar, rice etc from the bulk bins and loved it. They even give you a 10 cent discount if you bring in your own tupperware.
I second the quality of Lhasa Karnak's spices. Their teas are fantastic as well!
Use Ball mason Jars when buying from bulk. They're work beautifully. The half pint size would be perfect for spices. Not only that but they serve double duty as drinking glasses. The kids use the half pint size and the adults use the pint size. And when one of the kids doesn't finish their milk, they simply put a lid on the glass and put it in the fridge for later. How cool is that...!