Spacking one Wagon implies that you used an over the top amount of force where usually less than 5% of the force you used would have done the job just as well. Thus Spacking the Wagon of your target.
"LollArz! Did j00 s33 me bring teh Spack Wagon down on his Behindage?"
A Modified bus, car, MPV or similar that has the capacity to safely carry retards (Known as Spackers).
That Spack Wagon has very clean wndows.