I'm pulling top rated nature scenes from r/EarthPorn on a constant basis into my Google Drive (which is set up as a local drive using Google Drive for Mac), then I set my wallpaper to cycle through them every 30 minutes. Glorious.
If
New hot post in subreddit
This Trigger fires every time a new post becomes one of the ten hottest posts in the subreddit you specify.
Then
Upload file from URL
This action will download a file at a given URL and add it to Google Drive at the path you specify. NOTE: 100 MB file size limit.
Explore more great ways to automate Reddit and Google Drive