An abstract texture of water. It's not perfect, but will do. You may download if you like it.
Source V. Hartikainen
Prismatic Hexagonalism Pattern No Background
Source GDJ
A fun-looking elastoplast/band-aid pattern. A hint of orange tone in this one.
Source Josh Green
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Prismatic Abstract Geometric Background 4
Source GDJ
8 by 8 pixels, and just what the title says.
Source pixilated
From a drawing in 'Less Black than we're painted', James Payn, 1884.
Source Firkin
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy