By popular request, an outline version of the pentagon pattern.
Source Atle Mo
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
A free seamless background with pink spots.
Source V. Hartikainen
As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin