My home made and painted Ork gobsmasha. I used the templates from the Vehicle Manual. I've had a couple games with it and love love love it ! for 100 points is a definetly Big Dakka Gun for my Ork Boyz.
A few pictures of in progress and for size comparison. I photocopied the templates. I used matte board for the majority of it. Popscicle sticks for the treads and odds and ends bitz and extras from my vehicle parts box.
Happy Gaming.