The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
The name tells you it has curves. Oh yes, it does!
Source Peter Chon
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
Number five from the same submitter, makes my job easy.
Source Dima Shiper
It looks very nice I think.
Source V. Hartikainen
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
A seamless tessellation pattern. To get the tile this is formed from, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
You guessed it – looks a bit like cloth.
Source Peax Webdesign
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim