We think that Kindles are great. They allow you to take almost all of your books with you when you aren't at home, which is a great thing when you are traveling, a student, or on the go a lot of the time. The only trouble is that the Kindle functions as a limited device because of Amazon.
Now, you wouldn't want to go messing about with your precious Kindle if you aren't experienced with electronics. However, this is a really neat add-on that will make your own Kindle easily hackable. You'll be able to extend its support quite easily. This mod puts a Bluetooth received into your Kindle.
The main reason behind this hack is the lack of support by Amazon for viewing PDF documents and PDF table of content pages on the Kindle. The easy way to do this is to access the Kindle via Bluetooth, so that all of the mods and adjustments can be done wirelessly. This keeps your Kindle pristine and un-modified-looking.
You'll need to open up the Kindle and modify the case, as well as remove a little internal plastic shell to make room for the Bluetooth dongle. You'll also need to solder it in. Once you've done so, it's detailed fully over at Griffin, you'll be able to install a bunch of 3rd-party software tools that Kindle-hackers have come up with. The article over at Griffin details this build quite fully.