Powerful computer applications today allow manipulating and fabricating digital objects in unimaginable ways. However, these tools are often sophisticated and very difficult to use. One of the challenges in graphics and design today is to create simpler tools that allow even novice users to use computers more naturally for photographs and 3D objects manipulations. In this talk I will present several such efforts. The key idea in all of them is to utilize humans specifically for semantic, high-level tasks that are very simple for them, but are still extremely difficult for machines, while utilizing the machine for tasks that are harder and tedious for humans.