Here is a preview of something I will be adding to the Walkerman program. Using MEL, and a wee bit of trigonometry, here is a spider, the legs are animated based on the movement in the positive x direction. I'm not to sure I want to bother taking the time to code it so you can move it in any direction, unless I can come up with a simple way to do it.

As it is coded now, the main joint x and z coordinates are used as references to move all the legs. . . .