Street markets. There are several taking place on different days. One is on Tuesdays and Saturdays in Via Garigliano and one is on Saturdays (I think) near Navigli. I think there's one near Porta Romana as well, but check it on the Web. There's a lot of cheap, bad-quality stuff, but you can also find designer stuff at ridiculous prices (old collections). Fantastic shoes for under 20 euros and such. Even if you don't find anything, those markets are still great fun.
These streets (Via Torino and Ticinese) are touristy, but there are some interesting shops nevertheless (young designers, hand-made shoes): http://ciaomilano.it/e/shops/torino.asp
''I saw JJ in her prime.
Another time, another time.''
By Harold Pinter&Brena
Fashion is the city's biggest draw. A great location for everyday shopping is the Corso Buenos Aires. A wide, busy, major street in north-eastern Milan, it's everything you need from a high street - clothes, shoes, accessories, department stores, cafes, DVD etc...