Reference Management Software
In every course that I teach I make it a point to stress the importance of a good literature and reference management system (LRMS) for students and researchers. I'd argue that there are few tools that have an equal impact in making your life easier at a university. A good LRMS will help you organize your literature, read your articles, and write term papers or manuscripts. It's always surprising to me that even in M.A.- or Ph.D.-level courses students are not using a system and have never heard of them.
The basic logic of LRMS is that you use the software to organize your readings. Instead of several literature folders based on classes or projects you (usually) have one large folder for all your readings and the LRMS allows you to organize the PDFs. In some (most) systems you can even add your notes and comments to the articles. This means, that a LRMS allows you to have all your readings in once central location. Additionally, almost all LRMS generate a bibliography file for you that you can use to add citations to your term papers or other manuscripts. If you write in LaTeX you can use the .bib file generated by most reference systems to automatically include citations and generate your bibliography. If you write in Word or a Google Doc you can use the plugins from some LRMS (e.g. Mendeley or Zotero) to add citations and automatically generate bibliographies. This is a HUGE time saver - no more searching for proper citations to articles online and also no more manually adding entries into your bibliography at the end of the document.
Wikipedia has a great list of literature and reference management software here. Mendeley and Zotero are very popular choices. However, I'd like to point out that Mendeley might be free (as in free beer) but is not Free Software (as in free speech).