A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
A free seamless background texture of "timber wall" (colored in dark brown).
Source V. Hartikainen
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Did anyone say The Hoff? This pattern is in no way related to Baywatch.
Source Josh Green
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Just like your old suit, all striped and smooth.
Source Alex Berkowitz
This was formed by distorting an image of a background on Pixabay.
Source Firkin