Some friends and I pitched in for an Amazon Prime upgrade a couple months back and it's completely changed my shopping habits. Instead of browsing around trying to choose $20 worth of items to buy so I can get free shipping, I treat Amazon like a just-in-time supply delivery system. If my photo printer tells me it's running low on yellow ink, I quickly log into Amazon, order the $10 cartridge with free 2-day shipping, and by the time the ink is dry and new cartridge is waiting for me at my door. For gift buying, I can ensure precision gift delivery with the 2-day shipping, or overnight for an extra $4 when I'm really doing "just-in-time" shopping.

The resupply isn't quite perfect yet. Today I had to go to Home Depot to pick up replacement bulbs and a new light switch. It would be nice to envision a future in which, via RFID or by taking a photo of the item, I could save myself the effort of combing Home Depot's aisles and instead have the replacement parts waiting for me on my doorstep, delivered by my just-in-time Amazon supplier.