Skyscanner - Skyscanner.com compares over 1000 airlines to find you the cheapest airfares, fast.
Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
FlyGRN - Flight search engine that offsets carbon emissions for free
Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.
bliss - For music lovers, having an enormous selection of music on your computer is a no-brainer. Whether it's to help you get through work or charge through a work-out, you have music readily on hand. Read more about bliss.
JabRef - Graphical Java application for managing bibtex (. bib) databases.JabRef · JabRef Help · JabRef | Blog · OpenOffice/LibreOffice .