A seamless pattern formed from a sports car on clker.com. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
Prismatic Curved Diamond Pattern 2 No Background
Source GDJ
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
Prismatic Hypnotic Pattern No Background
Source GDJ
This is the remix of "Background pattern 115" uploaded by "Firkin".Thanks.
Source Yamachem
Prismatic Abstract Geometric Background 4
Source GDJ
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin