A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
8 by 8 pixels, and just what the title says.
Source pixilated
Found on the ground in french cafe in kunming, Yunnan, china
Source Rejon
A seamless background tile of aged paper with shabby look.
Source V. Hartikainen
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
Geometric triangles seem to be quite hot these days.
Source Pixeden
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
Prismatic Hexagonalist Pattern No Background
Source GDJ
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian