Umm... I don't know if Final Writer works. I'd try and show various Amiga software for compatibility. If I was demoing, then I'd show PageStream, ImageFXv4 (although I don't have PPC modules), ArtEffect 3, Miami, IBrowse, Cinema 4D, Freespace, Delitracker...
Do you have any of the Superbundle software loaded up? You might want to show off FXPaint, ProStation Audio.
Others on my list would be the MOS versions of Quake, UAE, BOCHS, Mplayer (playing a DVD), FroggerNG (playing DivX), MAME, ScummVM and not to mention the Catweasel.
Then there is APDF, Voyager, Kayaa that you might want to show off along with the skinning options.