While I was away, a thank you letter from Patty over at Just Letter Rip, written in response to this, found it's way into my post office box. I was ever so delighted to receive it. Not only was the envelope fun and creative, it was made ENTIRELY from recycled goods.
The envelope itself was actually another envelope in a previous life! Patty flipped an envelope she received into an envelope of her own. She has blogged about the process on her site.