Shading windows from outside (awnings, shutters, etc) to keep house from overheating in summer
Down here in Texas, solar screens are the thing to have. They're simply black mesh panels that install over the outside of the entire window, and in addition to being basic bug and safety screens, they reduce the amount of sunlight coming in to the window. You can still see out very well, so unless this is a big all-glass window wall (in which case I'd use tinting film similar to car windows) it's the thing to use.

Insulating, light-blocking curtains are another way to reduce solar gain. Yes they're inside, but they still work. Only problem is that you can't see through them.