WF Modifier: 3D-focus-control
Knowing the F-number of the final focussing optic, one can calculate the X/Y-tilt and defocus necessary to move the focal-spot about a specific distance in space, given in micrometers. This might be a cool feature.
Inspired by Imagine Optics :-)
EDIT: As wavefront modifiers are now used, this would be the proper way to implement that.