A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
This background texture resembles stone. It may be used as a background on web pages or on some of their html elements (header, borders, menu bar, etc.). Just modify it for your needs.
Source V. Hartikainen
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Abstract Geometric Background 5
Source GDJ
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
Here's a quite bright pink background pattern for use on websites. It doesn't look like a real fur, but it definitely resembles one.
Source V. Hartikainen
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857
Source Firkin