This isn’t something I’m really proud to post here since it takes only couple of hours to build such a node. Anyway, let me explain what it does and why it is made.

First of all, this node is just an alternative solution for scenarios which use a stretchy single chain IK joint. Now, this is what this node is composed of, 

1: It requires 3 matrix input by default, startMatirx, endMatrix and an upMatrix to determine the twist. For lazy guys like me, I have added an auto upMatrix option so that it will determine a non static upVector automatically.

2: Stretch limits(minimum and maximum)  can be applied as expected.

3: For dealing with scalable rigs, it has a globalScale attribute to compensate the output with rig scale. Again the laziness dominates, hence there is an autoScale option which can automatically determine global scale.

4: Can pin the output position in between start and end vector.

5: The intialLength attribute specifies the inital length between start and end position which is the base for all other calculations.  Ehmm, ehmm, I wouldn’t want to manually set this attribute everytime I create this node. So, this attribute will be automatically set once we provide proper input matrices.

I think it would make more sense if you see what it does rather than I explain all these here. Here is the video demonstration for the things I explained above

Thank you for your time.