Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
The image depicts a seamless pattern of Japanese Edo pattern called "kikkou-matsu" or "亀甲松" meaning " tortoiseshell-pinetree".The real pinetree is like this: https://jp.pinterest.com/pin/500744052301065077/
Source Yamachem
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
Prismatic Polyskelion Pattern No Background
Source GDJ
Prismatic Snowflakes Pattern 3 No Background
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Colour version of the original pattern.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Retro Circles Background 7 No Black
Source GDJ
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
A seamless texture of black leather. I think it will look best when used in headers, footers or sidebars.
Source V. Hartikainen