Unsplash Instant displays a beautiful high-resolution photo each time you open a new tab, which is free to download and use however you want. The images make great desktop wallpaper as well as gmail and calendar themes. (Just showing off my almost "inbox zero" 😁).
Make GIF Video Capture allows you to create GIF animations from any HTML5 video inside of your Chrome browser. It adds an additional button to in the YouTube video player. GIFs are images that can be inserted into gmails and google docs.
Anyone Can View is a Chrome Extension from Alice Keeler that allows you to change the share settings in an open Google Doc, Sheet, Slide, or Drawing to Anyone Can View and automatically copies the sharing URL to the clipboard.