Context Pie is a Blender add-on that swaps the traditional context menu for a context-sensitive pie menu, letting more functions sit on the same hotkey. It maps most functionality onto three shortcuts: Right Mouse for a mode selection pie, Shift + Right Mouse for the context-sensitive pie, and Ctrl + Right Mouse for pivots and node links. Because pie menus rely on directional muscle memory, they get faster to navigate over time.
The add-on brings pie menus to poly modeling, curve editing, UV mapping, node editors and animation, with operations placed sensibly across each context. The top option adapts to what you're doing: Merge in Edit mode, Join in Object mode, and Make Segment between selected points in Edit Curve mode. It's built to work well with Blender's industry compatible keymap.
Version 0.9.51 adds experimental node editor pie menus across the Shader, Geometry and Compositor editors, heavily integrated with the Node Wrangler core add-on and including custom operators to change Mix and Math modes. These node menus can be disabled separately in preferences. Context Pie is released under the GPL v3.0 or later and requires no special permissions.