Something like this in the front room. (Different colors) Plywood, Painters tape, and different paint colors. I can't wait to see the look on people's faces when I say, "Yeah, it's just a little something I threw together one day while bored.
You can easily make your own with a canvas, a paint brush, masking tape, and three colors + white acrylic paint. Just tape up your canvas every which way, paint a gradient of each color in the taped segments and remove the tape