Dark blue concrete wall with some small dust spots.
Source Atle Mo
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
No relation to the band, but damn it’s subtle!
Source Thomas Myrman
Clean and crisp lines all over the place. Wrap it up with this one.
Source Dax Kieran
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
A white version of the very popular linen pattern.
Source Ant Ekşiler
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
A light gray background pattern with seamless fabric-like texture and almost unnoticeable stripes.
Source V. Hartikainen
Produced using the clouds, flames and glass blocks plug-ins in Paint.net and the resulting .PNG vectorised with Vector Magic.
Source Firkin
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen