Constrain an object to time
A quick useful constraint system. Constrain an object to another in time. Works like a Parent Constraint, with time as an added variable.
To use simply copy paste the code below into a shelf icon. Then use it as you would any other constraint. Select the driver, then the driven objects and press the button.
A new attribute will be created on the driven object for each axis constrained. A value of 0 means to follow perfectly. Just like a parent constraint.
A negative value means to move that many frames delayed in time. A positive value means to move that many frames into the future.