The original enhanced with one of Inkscapes's filters.
Source Firkin
Colourful background achieved with gradient fills.
Source Firkin
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
White handmade paper pattern with small bumps.
Source Marquis
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Derived from a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Danmarks Riges Historie af J. Steenstrup, Kr. Erslev, A. Heise, V. Mollerup, J. A. Fridericia, E. Holm, A. D. Jørgensen', 1897.
Source Firkin
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
Prismatic Basic Pattern 2 No Background
Source GDJ
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
Looks like an old rug or a computer chip.
Source Patutin Sergey
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo