I'm not so sure version 1 of the $359 device will be a blockbuster, especially since it has at least one crucial shortcoming, in my opinion -- the lack of an illuminated screen.

It's hard to read a Kindle in the shade, and you can't read it at all in dark places -- like in bed -- unless you have an external light source. Yes, you need a light for real books, but the Kindle's an electronic gadget so you expect it to have its own light source.

Amazon must have been thinking the same thing, because it recently received a patent for an accessory reading light for the Kindle. The gadget is described as a "stowed reading light" and has the Kindle's angular style.

It was designed for Amazon by ATL Technology, a Utah designer and manufacturer of electronic components. An executive there told me the light was designed for Amazon's e-book.

The patent was filed in March 2007 and granted last month, but it's not clear whether Amazon plans to produce the Kindle light. I'm waiting to hear back from a spokesman, although I'm not expecting a lot of comment from the secretive company.

Also unclear is where you would stow a light on a Kindle, since the reader doesn't have any obvious cavities.

But it's intriguing, especially from a business perspective. Even if Amazon doesn't sell as many Kindles as some expect, it could grow the business by selling accessories. Or it could do better than analysts like Mahaney expect, if accessories supplement device sales. Mahaney was talking about just the device and content when he predicted Kindle will be a $1 billion business for Amazon in 2010.

Or perhaps Amazon is being cautious about the light. By selling an external reading light, it would be highlighting the Kindle's lack of illumination. It might also tick off buyers who believe a light should have been included in the first place.

Amazon will probably offer Kindle accessories eventually, but maybe we'll hear first about Kindle 2.0. By the holidays, perhaps?

Here are images of the "stowed reading light" that Amazon patented: