I wish I could remember where I saw this clever fold! If you featured it on your blog recently, please let me know so I can give you credit!
Please see both of my posts for the front and inside of this card. To make the fold, you start with a 4" x 12" piece of cardstock. Score at 4" and 8". Then score a diagonal line from the top of the left-hand score line to the bottom of the right-hand score line. Fold on the diagonal score line for the pocket, then the two vertical lines to make the card. Place 2 brads where shown, through two layers of cardstock, and then Sticky Strip under them to hold the pocket in place. Decorate as desired, and voila! This makes a 4" x 4" card. A cute card to hold a gift card, money, or a check.