Amazon.com knows my tooth brushing habits

Amazon.com knows a lot about me. They know what kind of books I like to read, what genres I buy the most and who my favorite authors are. They also know what brand of digital cameras, camcorders and computers I buy the most.

But would you be surprised if I told you that Amazon.com knows when my electric toothbrush needs a new replacement head?

Don't be.

Earlier this week, two Sonicare replacement brush heads showed up on my front doorstep courtesy of Amazon.com and UPS. Perfect timing. My current brush head was starting to look pretty worn.

How did they know?

So how exactly did Amazon.com become the next Carnac the Magnificent? It's actually not rocket science. Rather it's Amazon's Subscribe & Save service.

About a year ago, I placed an order for these same replacement brush heads. That's when I activated the Subscribe & Save option which tells Amazon.com to create a standing order for the item based on a regular interval. For my toothbrush heads, I opted to have a new order generated every 6 months.

Save money while you're at it

An added benefit of doing this, besides the fact that you don't have to remember to place another order every 6 months, is that Amazon usually gives you a discounted price when you use the Subscribe & Save option. That's the Save part. In the case of my toothbrush heads, Amazon gives me a 15% discount.

The only downside to this is that each time an order is generated, it is generated at the current market price for the item. I suppose I could shop around each time instead to find the absolute best price but a dollar or two extra here and there isn't enough motivation for me to want to make the effort to remember to manually place an order every 6 months.

And if you're wondering what happens if I eventually get rid of my electric toothbrush, don't. Amazon.com sends an email out a week or so before each order is placed giving you ample opportunity to cancel the order or the subscription if you no longer want or need it.

I wonder what's next. Will Amazon.com eventually come to my door every day to brush my teeth?