A textured orange background pattern with vertical stripes.
Source V. Hartikainen
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Wasn't satisfied with the original's colouring. Too much component transfer and colormatrixes yet the results are lacking a bit. So this time it is a simple black to transparent fade, making it possible remixing easily once there will be other blending modes supported as well. Probably in inkscape 0.92.
Source Lazur URH
From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib