In case anyone is interested in getting some Dreamcast related wallpapers for their PS Vita, I've created a site formatted for the Vita with some wallpapers. I mainly made it for myself but anyone can use it if they like.
Just type in this URL in your PS Vita browser: sites.google.com/site/dcvitawallpapers
It can be viewed on a PC as well but it's easier to just grab the wallpapers using the Vita's browser. There are currently only five wallpapers on the site but I may add more later.