Do you see large digital purchases of music, videos, and books in your future? Perhaps you're on the prowl for some iOS and Mac apps? If that's the case, you might be interested to hear that Walmart is selling a $100 iTunes gift card for $80, and, best of all, it's a digital certificate — no need to pay for shipping fees or wait for it to arrive in the mail. Despite the name, the card will work towards all purchases from the iTunes and Mac App Stores, as well as for media content directly from iTunes or the iBookstore. The whole process isn't supposed to take more than 48 hours, and if you're looking for something to buy with that credit, be sure to check our editors' favorites.