Prismatic Hypnotic Pattern 2 No Background #573
 Noise  CC 0

Prismatic Hypnotic Pattern 2 No Background

Source GDJ

 More Textures
Prismatic Octagonal Background@2X #440
 Noise  CC 0

Prismatic Octagonal Background

Source GDJ

Background pattern 231 #2301
 Dark  CC 0

A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Orange Gingham Checkered Background #258
 Stripes  CC 0

From PDP.

Source GDJ

blue wave-seigaiha #2535
 Blue  CC 0

The image depicts the Japanese Edo pattern called "seigaiha" or "青海波" meaning "blue -sea- wave".I hope it's suitable for the summer season.

Source Yamachem

Patchwork Quilt Pattern Background #228
 Noise  CC 0

PDP

Source GDJ

Dark Circles #306
 Dark  CC BY-SA 3.0

People seem to enjoy dark patterns, so here is one with some circles.

Source Atle Mo

Lead glass tile #2048
 Colorful  CC 0

Mostly just mucked about with the colours and made one of the paths in the lead frame opaque. The glass remains transparent.

Source Firkin

Green Gobbler@2X #86
 Dark  CC BY-SA 3.0

Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.

Source Simon Meek

Prismatic Groovy Concentric Background 4 No Black@2X #464
 Noise  CC 0

Prismatic Groovy Concentric Background 4 No Black

Source GDJ