An all leather bag is never cheap. Then again, there are two kinds of expensive items one should splurge on: timeless pieces that look good with everything in your wardrobe, and well-made stuff that lasts forever. A leather satchel is both and the bag seems to be everywhere right now. Billykirk crafted one in Horween leather especially for Need Supply, J.Crew offers a soft, washed version and Lotuff's double-gusseted style is ideal for gents with a lot on their plate (and extra dough in their pocket). With its English schoolboy roots, the satchel has an old world charm but inside, today's bags boast features like smartphone sleeves, business card pockets, laptop dividers and removable straps—which turn the shoulder-slung bag into a smart briefcase.