Thanks for the link, Patricia! The reason I was asking is that I've been taking a photo art course, which includes making brushes and the like with Photoshop... Just struck me it would be fun to see them on a web page.
(I made one last night that _I_ would consider startling --
https://www.wikitree.com/wiki/Space:Collection_of_photos_for_S_Banks_Tree_pages -- but I like it, so put it on that out-of-the-way free space page... Four of the other pix there are of locations, but there is another background with tiny, pale cliff swallow, which is hardly startling at all...)
I am just getting my head around this, and the visual aspects, etc., so will likely set up a page for backgrounds then and keep separate from other photos. (I find that plain white and pale grey screen create too much glare; hard on my eyes. And my monitor is calibrated for photo editing, so I don't much feel like making many changes there.)