TubeLister - Generate a YouTube playlist from your opened tabs.
Bookmark OS - Bookmark OS is like Mac or Windows optimized for bookmarks.
OrganizeTube - Create video playlists from Youtube, Vimeo and other sources
BookmarkSheet - Your bookmarks in Google Sheets
Learnamic - Free and paid K-12 learning resources from hundreds of providers, including educational apps, YouTube videos, online classes, printable worksheets, and more.
Annotate.tv - Optimize your learning on YouTube