MAYA // toggle click and drag

selectPref -clickDrag (!`selectPref -q -clickDrag`);
useful for animation in some case to click and drag an object with one click

MAYA // procedurally extrude all faces even if topology change

Useful for adding thickness to animated mesh, add an extrude then edit the component list :
setAttr "polyExtrudeFace4.inputComponents" -type "componentList" 1 "f[*]";
source

MAYA // offset an animation with a node - frameCache

to offset an animation with a node, create a frameCache node, connect an animated channel to its stream channel, and use the past or future values for the offset.
Connection has to be done with scripting :
connectAttr frameCache1.past[14] key.translateY; -> will offset of 14 frames
source

MAYA // Twist start end IK spline without advanced twist controls

twist from start :
set attribute on ikHandle like this : twist = roll * -1
for example, roll=150 and twist=-150

setup exemple where MD_invert_roll_1, input2X is set to -1