Thing 14 talks about referencing tools, namely freely available downloads such as Zotero, Mendeley and Citeulike. I've not used these myself but have read some comments from those who have, and my impression is that there is no one perfect solution for free reference management but you may find that one of these fits your particular need.
In my day to day work I use RefWorks as this is the tool used by my institution. It works well and makes my job easier and quicker -I handle a large number of references whilst working on a different potential and current research projects. Using Refworks means that I can collate all my references and go back to them at any time, insert them in documents and produce lists of articles of interest for the senior researchers.
I wasn't completely enamoured with Refworks initially. I used Endnote when I wrote my Masters dissertation and found this to be far more intuitive to use (one of my pet hates is reading instruction manuals, so anything I can use by just 'figuring it out' gets my vote!). In contrast, I found Refworks clunky and I needed to use the help menu, even though I was familiar with how a referencing system worked.
What saved Refworks for me was the fact that there is a compatible web based version in which you can create an account, and then import or export references with your desktop version of Refworks. This is great when working at home as it means I can import or export all my refences to one place and I don't have to be using my work PC. The web based version is also free.