Concrete Wall 3 #93
 Light  CC BY-SA 3.0

All good things come in threes, so I give you the third in my little concrete wall series.

Source Atle Mo

 More Textures
Paper 1 #15
 Paper  CC BY-SA 3.0

A slightly grainy paper pattern with small horizontal and vertical strokes.

Source Atle Mo

Squares #302
 Dark  CC BY-SA 3.0

Dark, square, clean and tidy. What more can you ask for?

Source Jaromír Kavan

Background pattern 19 (outline) #204
 Light  CC 0

A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.

Source Firkin

Circles@2X #186
 Light  CC BY-SA 3.0

One more sharp little tile for you. Subtle circles this time.

Source Blunia

Prismatic Hypnotic Pattern No Background #571
 Noise  CC 0

Prismatic Hypnotic Pattern No Background

Source GDJ

Old Mathematics #43
 Stripes  CC BY-SA 3.0

This one takes you back to math class. Classic mathematic board underlay.

Source Josh Green

Dark Blue Gray Wallpaper Texture #901
 Stripes  CC BY-SA 3.0

This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!

Source V. Hartikainen

Background pattern green #1944
 Green  CC 0

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

Source Firkin

Background pattern 208 (colour 2) #2462
 Grid  CC 0

A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin