Slowly but surely, dress-down Fridays have infiltrated the rest of the week. The line between work clothes and workout clothes has blurred, giving rise to a more dominant trend of business casual. Taking this cue, designers have started translating the nine-to-fiver's practical day bag -- in classic shapes like the duffel (above) and the backpack -- into sporty nylon. "A bag now has to combine both form and function," says Durand Guion, vice president and men's fashion director for Macy's. "It's durable, has a techy energy, and feels modern."
1. Gray nylon weekender bag by A|X Armani Exchange, $115
2. Orange bag by Emporio Armani, $595
3. Nylon damier pachable duffel bag by Louis Vuitton, $1,070
4. FS duffel bag by Y-3, $245