Could be paper, could be a Polaroid frame – up to you!
Source Chaos
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
It looks very nice I think.
Source V. Hartikainen
A dark one with geometric shapes and dotted lines.
Source Mohawk Studios
This pattern comes in orange, and it looks as if it is "made of glass".
Source V. Hartikainen
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
Dark blue concrete wall with some small dust spots.
Source Atle Mo
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
ZeroCC tileable wood boards texture, photographed and made by me. CC0
Source Sojan Janso
The classic notebook paper with horizontal stripes.
Source Are Sundnes
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin