Checkered Light Emboss #280
 Grid  CC BY-SA 3.0

Sort of like the Photoshop transparent background, but better!

Source Alex Parker

 More Textures
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

Felt #300
 Wall  CC BY-SA 3.0

Got some felt in my mailbox today, so I scanned it for you to use.

Source Atle Mo

Background pattern 224 (colour 5) #2338
 Colorful  CC 0

To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Diagonal Noise@2X #182
 Fabric  CC BY-SA 3.0

A simple but elegant classic. Every collection needs one of these.

Source Christopher Burton

fishnet 02 #2473
 Dark  CC 0

This is a more minute version of "fishnet 01".The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.

Source Yamachem

Prismatic Polyskelion Pattern No Background #394
 Light  CC 0

Prismatic Polyskelion Pattern No Background

Source GDJ

Polonez Pattern #334
 Gray  CC BY-SA 3.0

A car pattern?! Can it be subtle? I say yes!

Source Radosław Rzepecki

Tileable Wave Pattern 2 remix #2490
 Dark  CC 0

This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.

Source Yamachem

Background pattern 264 #2071
 Orange  CC 0

The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Retro Squares Background 2@2X #417
 Noise  CC 0

Retro Squares Background 2

Source GDJ

Soft Kill@2X #319
 Dark  CC BY-SA 3.0

Pattern #100! A black classic knit-looking pattern.

Source Factorio.us Collective

Bright Squares #87
 Light  CC BY-SA 3.0

It’s okay to be square! A nice light gray pattern with random squares.

Source Waseem Dahman

Paven@2X #297
 Grid  CC BY-SA 3.0

A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.

Source Josh Green

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 Geometric Pattern Background 2 #409
 Noise  CC 0

Prismatic Geometric Pattern Background 2

Source GDJ

Psychedelic Geometric Background No Black #382
 Noise  CC 0

Psychedelic Geometric Background No Black

Source GDJ