http://www.starfighter.acornarcade.com/mysite/utilities.htm#mbback

MBBack is yet another random backdrop chooser program to pick from the
myriad selection on the Internet.  What makes this one unique?  Well,
the headline features are:

- A user-editable script file containing a list of backdrops,
 automatically filtered for any errors or invalid filetypes.
- A 'compiled' version of this list, from which lines are removed after
 selection by the backdrop-choosing part.  This means the same backdrop
 is never chosen twice until all backdrops have been exhausted.
- Full ImageFileConvert support, copying each file to a sprite, hence
 allowing for a dramatic speedup in old versions of the Pinboard.
- Can select any sprite for display from within a sprite file, not just
 the first one.
- Built-in sprite scaling functions, capable of reducing (or enlarging)
 images to fit on the screen without the distortion associated with the
 Pinboard's 'Scaled' option.
- Facility to recalculate the current backdrop, for example if the
 screen mode has changed.

Sorry, you'll have to supply your own backdrops.

--
 __<^>__   "Your pet, our passion." - Purina
/ _   _ \  "Your potential, our passion." - Microsoft, a few months later
( ( |_| ) )
\_>   <_/  ======================= Martin Bazley ==========================