Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Prismatic Abstract Geometric Background 2
Source GDJ
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Prismatic Triangular Background Design Mark II 5
Source GDJ
From a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Remixed from an image that was uploaded to Pixabay by KirstenStar
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Pixel by pixel, sharp and clean. Very light pattern with clear lines.
Source M.Ashok
Prismatic Groovy Concentric Background
Source GDJ
A set of paper filters. The base texture is generated the same way, only the compositing mode is varied.
Source Lazur URH
A repeating background with wood/straw like texture.
Source V. Hartikainen
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
Lovely pattern with splattered vintage speckles.
Source David Pomfret
A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek