Seamless pattern formed from a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless paper background texture colored in pale yellow. This seamless texture is ideal for those who need a yellow background image for their website. The texture resembles paper.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
Original minus the background
Source Firkin
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
A background pattern with blue on white vertical stripes.
Source V. Hartikainen
A repeating background with wood/straw like texture.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green