Slidesgo - An extensive catalog of free Google Slides themes and PowerPoint templates.
VideoScribe - Make your own whiteboard video animations with Sparkol VideoScribe – award-winning video scribing app for PC, Mac and iPad. Free trial available.
SlideModel.com - Create attractive presentations with our professional PowerPoint templates, slide designs, and themes. Use our PPT templates and slide designs to give unique appearance to your presentation.
GoAnimate - Make your own animation quickly and economically with GoAnimate. Reach prospects and customers with animated videos online about your business and products.
SlideTeam - Transform rough sketches, notes into professional PowerPoint presentations.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.