A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
A blue gray fabric-like texture for websites. An yet another fabric-like texture. It has subtle vertical and diagonal stripes to it.
Source V. Hartikainen
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
A repeating background of thick textured paper. Actually, it turned out to look like something between a paper and fabric.
Source V. Hartikainen
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless web texture of "green stone".
Source V. Hartikainen
Fix and cc0 to get the tile this is based on.
Source SliverKnight
From a drawing in 'Kingsdene', Maria Fetherstonehaugh, 1878.
Source Firkin
Prismatic Snowflakes Pattern 3 No Background
Source GDJ
This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
Prismatic Hexagonalism Pattern No Background
Source GDJ
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
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