Stock markets be damned! Design-it-yourself handbags are the latest must-have on Europe's brand-infested boulevards. On Paris' flashy Avenue Montaigne, Ralph Lauren's sleek new shop features a corner where customers can choose from 20 shades of alligator and six linings to create their custom Ricky bag (starting at $12,995). On Milan's Via Spiga, the Tod's flagship boasts a Pashmy room where clients can choose the color, skin and hardware of their favorite bag (prices start at $925).