For all books - fiction and non-fiction.
A comrade has provided a presumably more long-lived link here.
On my Kobo Clara 2E, putting them all in .kobo\screensaver\ causes the reader to load a random image every time I turn it off. Probably works very similar for other Kobo readers.
Non-permanent links: link1 link2 link3. If all the links are dead at some point, I can upload again.
Honestly stolen from Paperback Paradise, @paprbckparadise@twitter, paperback-paradise@tumblr
Why is yugopnik black?
Maybe he is irl, you’ve never seen him, have you.
Good point
Link is dead
I'll reupload tomorrow, thanks for letting me know.
lmao good idea, my default screensaver is literally an ad for itself.
What device do you have? I have a Kobo H2O something and it doesn't have an option to choose it, it only defaults to whatever you're reading.
Its a pocketbook basic, looks exactly like its advertised on amazon lmao
Anyone know whether the same thing can be done with a Kindle?
Good for 11 months is it? 
New link up, but it's only good for a week.
lmao, these are funny. You've earned yourself a link at https://data2.encryptionin.space/fakecovers.zip
Edit: yes this is a permanent link.