Copy World Matrix 
Copy and paste the world matrix of an object or a bone. It recalculates also child of constraints, so it will always go back to the same position in world space.
It can work also with multiple objects and bones, and will copy and paste the matrix for each selection separatly.
Using the Filter Tools, it's possible also to copy paste only specific axes.

Paste To
- Current Frame - Paste the matrix only at the current frame.
- Selected Keyframes - Pasted to all the selected keyframes, also the handles will be adjusted to match the matrix during the inbetween frames.
- Frame Range - Pastes and bakes into a custom frame range.
- Selected keyframes Range - Pastes and bakes into every frame between the first and the last selected keyframes.

Using the markers range, it's possible to use the markers as widgets to setup the custom frame range, instead of entering numbers numerically.
Examples for Useful cases:
- Fix sliding legs for cyclic animation that move with a root bone.
- When switching between different setups or child of constraints, and things start to jump around.
- align object with bones.
Fixing Leg Slides
Locking the foot in space while the root control keeps moving forward
