PDFCreator is an open source alternative that lets you create Adobe PDF files. While it doesn’t have the advanced features contained in the latest Adobe Acrobat, it does pack enough power to deal with everyday PDF requirements easily.
http://www.makeuseof.com/tag/create-free-pdf-files-instantly-easily-pdfcreator/
DawsonITE is a blog devoted to Educational Technology. It's compiled by Rafael Scapin, Coordinator of Educational Technology at Dawson College in Montreal (Canada).