Prismatic Polyskelion Pattern No Background
Source GDJ
Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A comeback for you: the popular Escheresque, now in black.
Source Patten
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868.
Source Firkin
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Colourful background achieved with gradient fills.
Source Firkin
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
One more sharp little tile for you. Subtle circles this time.
Source Blunia
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Prismatic Floral Background No Black
Source GDJ
Prismatic Groovy Concentric Background 4
Source GDJ
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Curved Diamond Pattern 4 No Background
Source GDJ
Prismatic Groovy Concentric Background No Black
Source GDJ
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Medium gray pattern with small strokes to give a weave effect.
Source Catherine