Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
A pattern drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
A brown metallic grid pattern layered on top of a dark fabric texture. It should look great when using as a tiled background on web pages, especially blogs.
Source V. Hartikainen
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
A seamless background colored in pale orange. It has a paper like texture with diagonal grid pattern.
Source V. Hartikainen
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
A heavy hitter at 400x400px, but lovely still.
Source Breezi
The image depicts a seamless pattern which was made using stripe-like things including borders.I used OCAL cliparts called "Blue Greek Key With Lines Border" uploaded by "GR8DAN" and "daisy border" uploaded by "johnny_automatic".Thanks.
Source Yamachem
From an image on opengameart.org shared by rubberduck.
Source Firkin
Subtle scratches on a light gray background.
Source Andrey Ovcharov
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Prismatic Hexagonalist Pattern No Background
Source GDJ
Looks as if it's spray painted on the wall. You can be sure that this pattern will seamlessly fill your backgrounds on web pages.
Source V. Hartikainen