This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
A new take on the black linen pattern. Softer this time.
Source Atle Mo
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
Can never have too many knitting patterns, especially as nice as this.
Source Victoria Spahn
A free seamless background with pink spots.
Source V. Hartikainen
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen