The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
f you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
A seamless background texture of old cardboard.
Source V. Hartikainen
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This texture looks like old leather. It should look great as a background on web pages.
Source V. Hartikainen
I asked Gjermund if he could make a pattern for us – result!
Source Gjermund Gustavsen
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
The image depicts a seamless pattern made using a bird's face.
Source Yamachem
Someone was asking about how to achieve a fur pattern at #inkscape irc so tried to make a filter on it. Flood filled fractal noises rigged together. May someone find a good use for these.
Source Lazur URH
From an image on opengameart.org shared by rubberduck.
Source Firkin
A repeating background with seamless texture of stone. There haven't been any stone-like backgrounds for a while, so I have decided to create one more. The rest can be found in the appropriate category.
Source V. Hartikainen
Here's a new background image for websites with a seamless pink texture. It should look beautiful with website themes where light pink background is needed. The background is seamless, therefore it should be used as a tiled background.
Source V. Hartikainen
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Classic vertical lines, in all its subtlety.
Source Cody L
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin