Many libreoffice presentation templates.
I am not owner or creator of any of those templates.
Mostly these files are licensed under a CreativeCommons or GPL License. If you have any problems with a file included here just contact me and I will remove it.
Templates extracted from:
libreoffice-impress-templates: https://github.com/dohliam/libreoffice-impress-templates
libreoffice-template-center: http://templates.libreoffice.org/template-center?getCategories=Presentation&getCompatibility=any
(NIX): If you want to install the templates systemwide:
cd dir
sudo find . -type f -name "*.otp" -exec cp {} "/usr/lib/libreoffice/share/template/common/presnt/" \;