Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
Formed from decorative divider 184 in paint.net. Vectorised with Vector Magic.
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless light gray paper texture with horizontal double lines.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
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
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
A repeating background with dark brown stone-like texture and abstract pattern that looks like tree trunks.
Source V. Hartikainen
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges