Were there a lot of add ons and such for PPC back then? For instance, twelve south makes a few items for current iMacs and external HDD cases are made to resemble Mac minis and G5s/Pros.
Anything for an iMac G3 or G4 out there?
One thing that comes immediately to mind is the USB Imation "Superdisk" LS 120 drive that was similar in color to the Bondi Blue iMac and also looked good sitting on top of a B&W G3.
LS-120 drives can also read regular 3.5" floppies(back around the turn of the century my dad and I both used internal LS-120 drives our main Windows desktops as a complete replacement for a standard floppy drive), they were a convenient external floppy drive as well as high capacity portable drive for the systems that didn't have an internal floppy.
As it so happens, I have one sitting on top of the Quicksilver I'm typing this post from. It came from the same person who gave me a pair of G3 iMacs-both an original "Revision A" Bondi Blue 233mhz, and a later 600mhz Indigo. I don't use it all that often, but my dad and I both still have a lot of data kicking around on 3.5" floppies and on LS-120 disks. I think my Quicksilver is the only computer in the house now that can read LS-120 disks.