https://www.reuters.com/article/us-usa-holidayshopping-cybermonday/cyber-monday-set-to-become-biggest-u-s-online-shopping-day-idUSKCN1NV191 >Cyber Monday was on track to bring in a record $7.8 billion in U.S. online sales, but will also test the limits of retailers' e-commerce operations as millions of shoppers scour for steep discounts on everything from Lego sets to big-screen TVs.