The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
Looks like an old wall. I guess that’s it then?
Source Viahorizon
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
Gold Triangular Seamless Pattern No Background
Source GDJ
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin