Messenger bags, though ideal for messenging, might be too informal for a corporate job; at the same time, briefcases make you look like a stiff. For a classier but still casual carrying case, check out RoBags' new fall collection.
An NYC enterprise hq'd on 28th St, RB understands you need a bag you can flash in front of your company's CEO, but still haul into the bar without looking like you're using power-accessories to pick up leveraged buyout-groupies. As for functionality, RB's creative team of disillusioned architects has lined their computer-ready models thick w/ padding, while other bags have side pouches spacious enough for a wine bottle. They've also included pockets for everything from magazines to PDAs to MetroCards/dead MetroCards you think might one day magically self-recharge.
RoBags are pricey, but you'll be getting high quality, extremely durable nylon or leather that should last you twice as long as a lesser product -- or possibly even longer, 'til the only bag you need's one to zip over your cold, dead face.