Number five from the same submitter, makes my job easy.
Source Dima Shiper
Clean and crisp lines all over the place. Wrap it up with this one.
Source Dax Kieran
Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A textured blue background pattern with vertical stripes.
Source V. Hartikainen
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
A free tileable background colored in off-white (antique white) color.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Remixed from a drawing in 'Очерки Русской Исторіи въ памятникахъ быта', Petr Polevoi, 1879.
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Inspired by a design found in 'Konstantinápolyi emlékeim', Miklos Chriszto, 1893.
Source Firkin
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
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