This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
The image depicts a Japanese Edo pattern called "kanoko or 鹿の子" meaning "fawn" which has a fur with small white spots.
Source Yamachem
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
Tile-able Dark Brown Wood Background. Feel free to use it as a background image in your designs or somewhere on the web. By the way, the color seems to be close to Coffee Brown.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From drawing in 'Musings in Maoriland', Thomas Bracken, 1890.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Seamless Green Tile Background
Source V. Hartikainen
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The image depicts a seamless pattern which was made using stripe-like things including borders.I used OCAL cliparts called "Blue Greek Key With Lines Border" uploaded by "GR8DAN" and "daisy border" uploaded by "johnny_automatic".Thanks.
Source Yamachem
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Abstract Line Art Pattern Background
Source GDJ