By By MATTHEW BOYLE Bloomberg Wal-Mart will offer discounts on more than a million online-only items that customers then pick up at stores, part of an effort by the world's largest retailer to challenge Amazon. Taking another page from the Jet.com business it bought last year, Wal-Mart will first cut prices on about 10,000 web-only items such as Britax car seats and Lego toys, according to a statement.