Depending on whether you usually browse Amazon.com sober or Drunk, one-click purchases can be a gift or a curse; making those drunken purchases you will almost definitely regret the next day all the more easier to complete, or simply saving you the tedious process of filling out your C.C. and address information every-time you want to buy a USB cable online.
Amazon's admittedly life simplifying solution called "1-Click" saves you the trouble by having your "default" C.C. and address saved on record; finally allowing you to buy that new set of dumbells that you plan on using all summer long without the need to tire your fingers; all it takes is a click.
The really interesting part is that you've probably used this patent without even knowing it, because even the mighty Apple who bow down to know one pay royalties to Amazon for the honor of using their brilliant impulse purchase technique. Apple have implemented the 1-Click purchasing into both iTunes and iPhoto; which would probably explain why your 2-year old toddler is so good at wasting your iTunes credit.
Later on Amazon's rival Barns & Nobles tried making their own mock-up of 1-click called "express lane", the fine people at Amazon wasted no time taking them to court where the Judge ruled in Amazon's favor; reducing the poor shoppers at Barnes and Nobles to be forced to click a second confirmation button before completing their purchase. Oh the horror.