Another trick that I recently found out in connection with the kindle: if you want to send a PDF to your Kindle to your @free.kindle.com email address simply type “Convert” for the subject and add the PDF as an attachement. Amazon will then try to convert the PDF to an eBook suitable for Kindle
I’m using Feederator myself to send interesting posts to my Kindle to read it later. To do this you can simple drill into the detail view of a post. There you’ll find a social bookmarking widget, labled with “share”. In the popup select “more” and then search for instapaper. In order for this to work you need to setup an account at instapaper.com, but don’t worry, it’s free!