Of all the directions of light, perhaps there's no finer option than shooting directly into the sun. You can use it to bring landscapes to life, add visual interest to portraits, or highlight the color of a flower petal. Keep in mind, backlighting can be a tough scene for a camera to expose properly. If you're not comfortable with metering manually, take several shots using exposure compensation. Bracketing this way is a quick way to handle an otherwise tricky scenario. As you'll quickly see, the results are well worth the effort.
For more ideas on how to use the different directions of light, check my tutorial here.