If you're ready to step up your leather working game from basic strap and construction work, consider going all out and making one of these: a full-on leather doctor's bag-style briefcase.
Maker and designer Phiske shares that the doctor's bag here "refers to any bag that has an internal metal frame that is hinged to hold the mouth of the bag open." He points out that you can buys these, but they're pricey and don't work all that well to begin with. "So being a Maker, " he says, "I figured I'd make my own."
The results are a fine example of what a fellow and some tools can do. Get the full how-to, including the making of the new steel frame, at Instructables: