This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
ZeroCC tileable stone texture, edited from pixabay, CC0
Source Sojan Janso
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
This ons is quite old school looking. Retro, even. I like it.
Source Arno Declercq
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
Background formed from the original with an emboss effect
Source GDJ
Tiny little flowers growing on your screen. Nice, huh?
Source Themes Tube
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Another fairly simple design drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen