Miles and Michik both got it right, and Michik hit the bullseye. It's Nekobus, also known as Catbus, Nekobasu, or Neko no Basu, from the Studio Ghibli movie "My Neighbor Totoro." The model is by PODragon or Jyxxie, and can be downloaded in two sizes by following the link below:
Papercraft - Catbus by Jyxxie on deviantART