Project Managers and Lean implementers frequently have to make presentations.
Rowan Manahan has a great series Presentation Masterclass at Lifehack.org.
There was another great post by Phil de Kock published A Checklist for a Good Facilitation on pmhut.
If you liked that post, then try:
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I just saw another great post by Stacey Douglas at Undocumented Features called “Use Cognitive Science to Improve Your Presentations”
http://www.undocumentedfeatures.com/2008/05/12/use-cognitive-science-to-improve-your-presentations/
Great tips about visual presenting skills.