One of the really great things about the various nodes that Maya provides is that there are very few limits on how you use them. To Maya, all nodes are just collections of functionality with certain inputs and outputs, and as long as the type of data lines up, it doesn't really care how you connect them.
This means that it's completely possible (and often very useful) to use hypershade nodes for tasks that aren't related to creating shading networks. In this example, we'll be doing just that using a plus/minus/average utility node to set the position of a given object to the average position of a number of others. This could be used, for example, to ensure that the pelvis of a character always stays centered in between the IK handles controlling its feet.
Using utility nodes can be used for tasks where you might otherwise write an expression, but with the added benefit that they update constantly, not just while the playback head is moving.
