Torn between two (vastly different) colors for your room? Why decide?

I find myself drawn to these images, where homeowners have created a beautiful, visually arresting look by pairing two dissimilar colors on the same wall. Besides just adding interest, you can use this effect to play with the proportions of a room. Painting the top few feet of the wall the same color as the ceiling will visually shorten a room, making a large room feel cozier; painting the top of the wall in a contrasting color will draw the eye upward.

Shown Above:
1 & 2. Farrow & Ball via Simply Grove
3. Marie Claire Masion via Decor8.
4. Design*Sponge
5. Design*Sponge

Images: As credited above.