NXPowerLite 

NXPowerLite can reduce the size of your PowerPoint files by over 90%. It's fully customizable, allowing you to choose the ideal balance between compression and quality. This free, fully functional trial version will compress up to 10 presentations.
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PowerShrink 

Compress your PowerPoint files in 2 single steps. No more hassle sending those big presentations to your customers. No need for receiver to run additional software to view the compressed files. PowerShrink leaves all PowerPoint functionality intact.
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