iPhone

If you're like most people, your wallet contains far more cards than you use every day: grocery club cards, insurance cards, frequent flyer cards, and who knows what else? Here's a cool idea: Scan or photograph these cards and store them on your iPhone instead. The screen is large and crisp enough that you can even scan barcodes from it—so if you scan, say, a grocery store customer loyalty card, you can simply hold the image of the barcode up to the barcode reader and get your sweet discounts.