move window to whichever screen the mouse cursor is on

[mstorus]

Is it possible to have slate move the window to whichever screen the mouse cursor is on? This is the behavior I'm used to from Divvy.

I use two monitors (my laptop monitor and an external monitor). Given
bind a:alt;space push left bar-resize:screenSizeX/2
if I press alt-space a, I want the screen to be pushed to the left half of whichever screen my mouse pointer is on.
This is useful when I want to move a window from one screen to another.