Bulging Garden Hose Animation I am trying to create a setup that will let me send meshes along a path deforming a mesh that surrounds that same path. Pretty much like in a cartoon fluids travel on the inside of a strawer, bulging the strawer or garden hose or whatever object outward in the process. 

I have found a video that illustrates the concept, but it is a setup for 3DS and I cannot replicate that in Blender. 

https://www.youtube.com/watch?v=e0Iq_cTS1uo

So far, I have tried using the warp modifier, but that does not take the objects shape into consideration.

Is there a way to move one object through the other and displacing the outer object's vertices by those of the inner one?
The cast modifier should let you do exactly what is in the video, with only a couple of steps.

To set it up, you will need a hose object with fairly dense geometry, and an object to pass through the hose.

To set up the system, you will need to have the object (I'm going to use a sphere as an example since that was the object in the video) positioned at one end of the hose, and animated to move through it. I would think a curve would be the best way to animate the object, and you could also use the same curve to bend the hose.

Once you have the animation set up, simply add a cast modifier to the hose, select the sphere in the control object box and then adjust the radius until the hose completely covers the object.