Chrome: Pig Toolbox is a Chrome extension that features a bunch of different functions all rolled into one simple extension. It includes mouse gestures, a collection of YouTube-related tools, an automatic Google Mail checker and more.
As the name implies, Pig Toolbox is a collection of tools that all exist inside of one single extension so you don't have to have a bunch of different extensions filling up your toolbar. On top of the features mentioned above, Pig Toolbox also lets you configure a number of contextual shortcuts, take screenshots, create blocklists and plenty more. A number of the functions are Windows-only, but if Pig Toolbox happens to have features you use regularly, it's worth checking out. Find the full list of everything in the toolbox on the Chrome Web Store.