A while back, I found this link to a great little software program that is free to download. It allows you to print your own envelopes onto regular paper or cardstock and fold, then seal accordingly. You can enter in precise measurements so that you have the perfect-sized envelope for homemade cards, letters, bills (gasp!) or whatever else you need an envelope for! Uses a simple 8.5" x 11" piece of paper/cardstock.