Background pattern 215 #2371
 Brown  CC 0

A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.

Source Firkin

 More Textures
Background pattern 314 #1839
 Yellow  CC 0

The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Background pattern 227 #2314
 Yellow  CC 0

A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.

Source Firkin

Axiom Pattern #330
 Grid  CC BY-SA 3.0

Not even 1kb, but very stylish. Gray thin lines.

Source Struck Axiom

five yen-seamless pattern #2511
 Unknow  CC 0

This is the remix of "blue wave-seigaiha".The image depicts a seamless pattern of the front upper part of Japanese five yen coin which is used currently.This design represents a rice with ripe golden ears.

Source Yamachem

Decorative divider 217 #2233
 Dark  CC 0

Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.

Source Firkin

Abstract Ellipses Background Grayscale #378
 Dark  CC 0

Abstract Ellipses Background Grayscale

Source GDJ

Dark Leather #129
 Dark  CC BY-SA 3.0

You were craving more leather, so I whipped this up by scanning a leather jacket.

Source Atle Mo

Prismatic Floral Pattern 3 Variation 3 No Background #386
 Noise  CC 0

Prismatic Floral Pattern 3 Variation 3 No Background

Source GDJ

Medic Packaging Foil #376
 Light  CC BY-SA 3.0

8 by 8 pixels, and just what the title says.

Source pixilated

Checkered Light Emboss@2X #281
 Grid  CC BY-SA 3.0

Sort of like the Photoshop transparent background, but better!

Source Alex Parker