There were user-created means to apply wallpapers with earlier hacks, but for those of you checking out the new firmware it might be the first time you’ve tried them out. I just made this one for myself, but you’re welcome to it. I’d link the artist’s site, but last time I did that, I’m told that the rack which hosted her equipment burst into flames.
You can save it right out of the new browser, if you like. Just remember, for your own adventures: 480x272, put it in the PHOTO folder, and hit the Set As Wallpaper menu option in the Photo menu.