With a slightly bigger screen than an average cellphone, you can view Halo pictures like this on the go. This was created using SplashPhoto, a Mac and Palm-based image gallery system.
With apps like Graphic Converter and Backdrop GC (not pictured) you can make a file like this into a Fireviewer-compatible .pdb file and use it as a background image on a Palm if it has Palm OS 3.5 or greater.