Random Grid Brushes for Photoshop and Elements and PSP and Affinity etc (Volume 240) 200 Random Grid color brushes / patterns / symbols / EPS format
You may be also interested in the grid brushes set as well as the 100 themed grid brushes set (they are all subtle variants of the ones on this page). You may also find the vector grid fonts / eps designs of interest as they can be used with any size of work
If you want some tutorials on the artworks, please check out the tutorials sections for the brushes.
You can also tryout some freebie artworks / samplers