How do I slant adjoining edges? If I have a cylinder that is 1 inch tall, how can I slope the top from the front to the back down to, say, a quarter inch evenly? If I select all the edges or all the vertices, they just move down together. Not sure if that makes sense.
You can Shear the top of the cylinder by using Shift+Ctrl+Alt+S, then hit Y to shear Vertically or X Horizontally and adjust the amount of Shearing with the mouse or input a value, then hit Enter to apply.

Note that the mesh is Sheared relative to the view angle.