A comeback for you: the popular Escheresque, now in black.
Source Patten
This is sort of fresh, but still feels a bit old school.
Source Martuchox
Prismatic Groovy Concentric Background 4
Source GDJ
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Run a restaurant blog? Here you go. Done.
Source Andrijana Jarnjak
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin