Finding the right symbolic comparison is often more difficult than making the actual PowerPoint chart. In a series of "chart concepts" I will give some ideas how to represent common business concepts with images.
To show that something is torn by 2 opposing forces (for example laptop user mobility and computer security) you could use this iStockPhoto image.
After downloading/purchasing, paste it in PowerPoint and stretch it to full screen size and add a few big-font words on each side. Make sure not to distort the original width/height proportions of the image.
Disclosure: no commercial interest.