Hexagonal pattern (colour) #2378
Yellow CC 0A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
More Textures
Seamless Cardboard Texture #1212
Cardboard CC BY-SA 3.0A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen
Background pattern green #2027
Green CC 0Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light Aluminum #304
Wall CC BY-SA 3.0Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
Carbon Fiber Big #326
Carbon CC BY-SA 3.0Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
Tree and bird pattern #1983
Dark CC 0From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
White Wall 2 #1020
Wall CC BY-SA 3.0A new one called white wall, not by me this time.
Source Yuji Honzawa
Decorative divider 219 #2231
Dark CC 0Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Prismatic Snowflakes Pattern 3 No Background #413
Light CC 0Prismatic Snowflakes Pattern 3 No Background
Source GDJ
Flower Trail@2X #742
Noise CC BY-SA 3.0Sharp pixel pattern, just like the good old days.
Source Paridhi
Shapes decorative divider #1903
Colorful CC 0Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Fabric 6 (colour 5) #2591
Green CC 0An alternative colour scheme for the original seamless texture formed from an image on Pixabay.
Source Firkin
Mossy #1296
Stone CC 0ZeroCC tileable mossy (lichen) stone texture, edited from pixabay. CC0
Source Sojan Janso
Nami@2X #576
Dark CC BY-SA 3.0Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
Old Mathematics@2X #44
Stripes CC BY-SA 3.0This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Background pattern 232 #2297
Dark CC 0Heavily remixed from a drawing in 'Barbara Leybourne; a story of eighty years ago', Sarah Hamer, 1889.
Source Firkin
Floral background #1975
Colorful CC 0Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Egg Shell@2X #862
Light CC BY-SA 3.0It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
Rubber Grip@2X #102
Dark CC BY-SA 3.0A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
Absurdity #825
Light CC BY-SA 3.0Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
Corrugation@2X #766
Light CC BY-SA 3.0The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Background pattern 239 #2218
Dark CC 0To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background pattern purple #1952
Colorful CC 0To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Floral design 86 #1885
Dark CC 0From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin