Slides Carnival: http://www.slidescarnival.com/
Slides Carnival is a whole bunch of really nice looking, free presentation templates for Google Slides or PowerPoint. As the site says: “These designs cover all styles from playful and creative to formal and business presentations, and all templates are easy-to-edit. Use them freely for your own presentation needs, work right away in Google Slides or download the templates as a PowerPoint PPT file and continue working on your computer.” All they ask is you give them credit.
Another great feature is the content of the templates. Each template contains around 25 different slides, all with beautiful images, backgrounds and icons, instructions, inspiration and ideas on how to use and adapt them.
Thanks to Nina Ferry for sharing!