Books on communication and presentation skills
General presentation skills
Video examples with scripts and translation in many languages
Software alternatives to PowerPoint
Online presentations
Digital Copyright
A good discussion on copyright law and creativity by a Stanford Professor.
http://www.ted.com/talks/view/id/187
Improving pronunciation
http://www.uiowa.edu/~acadtech/phonetics/english/frameset.html
Improving listening and speaking
http://www.englishcentral.com/videos