This reminds me that I just discovered 3M no longer recycles its polyester transparencies. I called, and was told the company that did the recycling went out of business. Now I'll have to throw away the box of transparencies at work. Not good.
Update: I forgot to mention that I mailed all the Tyvek envelopes in a Tyvek envelope turned inside out. Efficient packaging! The weight was 7 lbs., 8 ounces, and postage was $12.17.