This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
A nice one indeed, but I have a feeling we have it already? If you spot a copy, let me know on Twitter.
Source Graphiste
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
Background pattern originally a PNG drawn in Paint.net
Source Firkin
A seamless pattern formed from miutopia's cakes on a tablecloth.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Prismatic Curved Diamond Pattern 2 No Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Geometric Pattern Background
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Pixel by pixel, sharp and clean. Very light pattern with clear lines.
Source M.Ashok
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
A free grid paper background pattern for using on web sites.
Source V. Hartikainen