Background pattern 314 (colour 3) #1837
Green CC 0The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
More Textures
Background pattern 215 #2371
Brown CC 0A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Decorative divider 186 #2560
Green CC 0From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
Random Grey Variations #69
Stripes CC BY-SA 3.0Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
Background pattern 117 #524
Noise CC 0A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
Source Firkin
Prismatic Basic Pattern 2 No Background@2X #448
Noise CC 0Prismatic Basic Pattern 2 No Background
Source GDJ
Fence 6 #2575
Wood CC 0A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Wavy tile #2024
Colorful CC 0Seamless tile drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Lined Paper #1034
Light CC BY-SA 3.0I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
Prismatic Abstract Geometric Background 5 #401
Noise CC 0Prismatic Abstract Geometric Background 5
Source GDJ