Bright Multicolored Floral Background@2X #560
 Noise  CC 0

Bright Multicolored Floral Background by Karen Arnold from PDP.

Source GDJ

 More Textures
Bright Multicolored Floral Background #559
 Noise  CC 0

Bright Multicolored Floral Background by Karen Arnold from PDP.

Source GDJ

Transparent Square Tiles #298
 Grid  CC BY-SA 3.0

The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.

Source Nathan Spady

Grilled Noise #581
 Fabric  CC BY-SA 3.0

You could get a bit dizzy from this one, but it might come in handy.

Source Dertig Media

Zodiac pattern (black background) #267
 Dark  CC 0

A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.

Source Firkin

Real Carbon Fiber@2X #287
 Carbon  CC BY-SA 3.0

Carbon fiber is never out of fashion, so here is one more style for you.

Source Alfred Lee

My Little Plaid@2X #333
 Light  CC BY-SA 3.0

Repeating squares overlapping.

Source Pete Fecteau

Background pattern 306 (colour 2) #1881
 Colorful  CC 0

Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.

Source Firkin

Prismatic Triangular Seamless Pattern III With Background #273
 Dark  CC 0

Prismatic Triangular Seamless Pattern III With Background

Source GDJ