Not really. You can save a presentation as a template (POT) file,
which will open an unnamed copy of the template, but these files
contain only masters, and no slides.
If you don't want others alter your presentation, the best way is
converting your presentationt to Flash, Flash is very difficult for
others to alter.
Some third party presentation tools could help you convert PowerPoint
to Flash, you could view more from the following link: http://www.sameshow.com/powerpoint-to-flash-pro.html#110 http://snipurl.com/ppt-swf http://www.pointcast.com