The edges of all the red objects line up either vertically or horizontally, but it doesn't appear so. Made from a square tile that can be got by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
Remixed from a PNG that was uploaded to Pixabay by k_jprather
Source Firkin
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen
The image is a seamless pattern of a fishnet.
Source Yamachem
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.
Source Firkin
Classic vertical lines, in all its subtlety.
Source Cody L
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A nice and simple white rotated tile pattern.
Source Another One
Remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
Here's a new background image for websites with a seamless pink texture. It should look beautiful with website themes where light pink background is needed. The background is seamless, therefore it should be used as a tiled background.
Source V. Hartikainen