If you think that SketchUp can only be used to create "straight" geometry (boxes, cylinders, nothing particularly organic or wacky looking), check out these two Dr. Suess-like models I found in the 3D Warehouse. Clicking on the graphic takes you to the Warehouse page where you can download the model.
(The model above has shadows turned on, which looks very neat but you can get your model to mode faster if you choose View / Shadows to turn shadows off.)
Anyone can design anything in 3D! www.3dvinci.net