Graphic and oh so simple, something like this black dots artwork could be done with paint on canvas or even with black markers on nice white paper. Signing it or writing a sweet message on the side is nice but not even necessary.
Also from DwellStudio is this black ink artwork. It, too, could be a DIY project but it would require a little more effort than the dots.
The gray, white and black color palette in these photos is perfect for my bedroom. So far I have my version of Franz Kline's artwork, the gray painted furniture, a reupholstered desk chair and there is one open area of the room just waiting for something like this:
all photos from DwellStudio