Microsoft Office 2013 has just been added to the Home Use Program, which enables employees of certain companies very cheap access to Office software for home use. With the appropriate business email address and a code from your employer, who must enable HUP through Software Assurance, you can purchase a copy of Office 2013 Professional Plus for as little as US$9.95. You are also able to download Office 2011 for Mac if you aren't a Windows user.
Naturally the price of Office 2013 varies between different regions, for example it's £8.95 in the UK and AU$15 in Australia, however it still comes in significantly cheaper than purchasing a standard retail copy. The most basic single-user Office package costs $139, and that doesn't include all the programs from the full Professional Plus edition you get through the Home Use Program; Professional Plus comes with Word, PowerPoint, Excel, Outlook, OneNote, Access, Publisher, InfoPath and Lync.
To make use of the program be sure to check with your employer to get the appropriate HUP program code, although if you're in the United States Army it's as easy as entering your official Army email address (@mail.mil, @us.army.mil, etc.) and then using the code C4FAA257E3. It's well worth checking out especially at the extremely low price.
Thanks for the tip, M