There's a gadget out there that may solidify the most lasting change in books since Johannes Gutenberg invented moveable type in the 15th Century -- and could save you a few bucks in the long run as well.I'm talking, of course, about the Amazon's ( AMZN) Kindle, which lets you download books, newspapers and other reading material instantly. I've never been a true "early adopter" of new technologies, and I don't write tech reviews. But the story of the Kindle has implications for both business and personal finance. Plus, think of all the trees we'll save. It all started when an email arrived announcing that Amazon had lowered the price on Kindle to $359 from the previous $399. I'd been hearing about this device, but I really wanted to see this thing before I ordered it. That turned out to be easy. Amazon has created a blog on their site that is actually creating local user groups. I posted a request to see one, and got a lot of responses. The posts were from people who offered to meet in some public place and give me a demo. Everyone who already had a Kindle raved about it. Comments ranged from explaining how easy it was to use and set up, to how much money they were saving on books (even bestsellers cost only $9.99) to how they were using their Kindle to save money on college texts. One devoted Kindle user explained she was making money selling all her used paper books! When my own Kindle arrived, I stared at the box, worried about the setup process. No problem. Even for me, it was easy. Within minutes I understood more about Kindle than I do about my new cellphone.