Magnetic Board... "Don't ask for "Sheet Metal" because that is super expensive...some were $40 a sheet. Go to the metal chimney or roof venting section. The pieces came in 2 sizes. This one was the largest 24" x 36" and they were only $5.00 and $7.00 each."
Make a magnetic chalkboard out of a picture frame to stick to the fridge for grocery lists. Using a picture frame means the chalkboard is easily removable and can be cleaned completely, right to the edges.