If you have an e-Reader like the Nook or the Kindle then you may want to download this piece of software. Both the Nook and the Kindle can view pdf files as they are already, however most e-readers don't read the pdf properly and it looks broken. With this software called "Calibre" you can import a pdf file, or a number of other different file types, and it will convert it to the epub format. This allows you to get your books for free if you know where to download them. I have a Nook e-Reader from Barnes and Noble. When you first start Calibre it will ask you what kind of reader you have. Select the one you have accordingly and now your ready to start importing books. When you import the book and right click it and click convert books, they will be available in the "/home/<your username>/Calibre Library" then you just have to connect your Nook, and transfer the file in the "my documents" directory in Ubuntu. This makes it so easy to get free books. Just download the book online in pdf format via a torrent, and you can enjoy free books without paying.
If you want to install this software, then open up a terminal and type:
sudo python -c "import urllib2; exec urllib2.urlopen('http://status.calibre-ebook.com/linux_installer').read(); main()"Make sure you copy the whole line that is in bold into your terminal and press enter. Don't forget to enter your root password. Once it is installed you can just run "calibre" from the terminal or, you can go into your Ubuntu menu and find it at Applications -> Office.