Sort of like the Photoshop transparent background, but better!
Source Alex Parker
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Honestly, who does not like a little pipe and mustache?
Source Luca Errico
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
I’m not going to lie – if you submit something with the words Norwegian and Rose in it, it’s likely I’ll publish it.
Source Fredrik Scheide
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
Source V. Hartikainen
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
I’m not going to lie – if you submit something with the words Norwegian and Rose in it, it’s likely I’ll publish it.
Source Fredrik Scheide
ZeroCC tileable wood boards texture, photographed and made by me. CC0
Source Sojan Janso
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida