I love the Longchamp Roseau previously mentioned, and the Prada Double-Zip is becoming a popular classic, but I don't know if the prada logo is too flashy. It's up for debate, but I don't like to show designer labels for interviews (anything above Coach seems too eye-catching), and for work, it really depends on the culture. I personally would not feel comfortable being the only one wearing an obvious designer brand to work, and prefer more under-the-radar look if bringing in expensive bags. I like Tod's and Mulberry Bayswater too. Anything with structure, can carry files and a laptop (if you need it), and nice quality leather are good choices. If you are willing to go quite casual and lightweight (everyday work bag), the black longchamp le planetes is a step above the colorful foldable version.