Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Prismatic Polyskelion Pattern No Background
Source GDJ
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Classic 45-degree pattern, light version.
Source Luke McDonald
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Background formed from the original with an emboss effect
Source GDJ
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Colour version of the original pattern.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
Tile-able Dark Brown Wood Background. Feel free to use it as a background image in your designs or somewhere on the web. By the way, the color seems to be close to Coffee Brown.
Source V. Hartikainen
Seamless Dark Grunge Texture. Here's a new grunge texture for use as a background.
Source V. Hartikainen
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
White circles connecting on a light gray background.
Source Mark Collins
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Number five from the same submitter, makes my job easy.
Source Dima Shiper