14. CardCash.comCardCash.com is a leading online gift card exchange allowing consumers to buy and sell discounted gift cards. CardCash allows budget-savvy consumers to purchase gift cards to their favorite restaurants, department stores and more all at discounts up to 35% off. For instance, a $100 iTunes gift card, which the company buys for $70, sells for $95 on the website. The company raised $6 million from Guggenheim Partners in November 2013.