Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
Sort of reminds me of those old house wallpapers.
Source Tish
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Polka Dots Mark II No Background
Source GDJ
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
The edges of all the red objects line up either vertically or horizontally, but it doesn't appear so. Made from a square tile that can be got by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A seamlessly tile-able grunge background image.
Source V. Hartikainen
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
A version without colours blended together to give a different look.
Source Firkin
A free light orange brown wallpaper with vertical stripes designed for use as a tiled background on websites. An yet another background pattern with vertical stripes.
Source V. Hartikainen
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ