I bought a black collage-type frame similar to this on clearance at Kohls for $8.
It sat in my closet for 6 months. When I redid my daughter's bathroom area last month, it needed some artwork to break up the blue color. Then I remembered our squares theme from her bedroom and that frame. I went to Hobby Lobby and bought a package of stickers that she liked and 4 different colors, patterns and textures of scrapbook paper: a green alligator texture, a black and glittery silver stripe, white dots on black, and a multi-colored square print that coordinated with her bedding.
For less than $15, we had a new, unique art piece that didn't break the bank!