The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.
Source Yamachem
Prismatic Groovy Concentric Background No Black
Source GDJ
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Plywood Web Background background image for use in web design.
Source V. Hartikainen
A good starting point for a cardboard pattern. This would work well in a variety of colors.
Source Atle Mo
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
This is the remix of an OCAL clipart called "Rain on Window" uploaded by "pagarmidna".Thanks.This is a seamless pattern of raindrops.
Source Yamachem
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen
Prismatic Polka Dots Mark II No Background
Source GDJ
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
Submitted in a cream color, but you know how I like it.
Source Devin Holmes
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
White little knobs, coming in at 10x10px. Sweet!
Source Amos
A seamless paper background colored in pale yellow.
Source V. Hartikainen
A bit of scratched up grayness. Always good.
Source Dmitry
This background image has seamless texture that resembles a surface of gray stone.
Source V. Hartikainen
Zero CC tileable Crackled Cement (streaks) texture, photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Inspired by a pattern found in 'A General History of Hampshire, or the County of Southampton, including the Isle of Wight', Bernard Woodwood, 1861
Source Firkin
Sharp pixel pattern, just like the good old days.
Source Paridhi
Prismatic Hypnotic Pattern No Background
Source GDJ