A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
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
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
I’m not going to use the word Retina for all the new patterns, but it just felt right for this one. Huge wood pattern for ya’ll.
Source Atle Mo
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Light and tiny, just the way you like it.
Source Rohit Arun Rao
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy