The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Floral Background No Black
Source GDJ
A nice one indeed, but I have a feeling we have it already? If you spot a copy, let me know on Twitter.
Source Graphiste
A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
An abstract texture of water. It's not perfect, but will do. You may download if you like it.
Source V. Hartikainen
Prismatic Groovy Concentric Background 2
Source GDJ
He influenced us all. “Don’t be sad because it’s over. Smile because it happened.”
Source Atle Mo
From a drawing of the coat of arms of the Ottoman Empire on Wikimedia.
Source Firkin
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers