Like most cameras would, it smashed into tiny pieces.
The lucky part was that only the screen broke, or in fact, only the LCD panel part of the screen broke. The electro luminescent panel (ELP) was unscathed, as was the plastic cover and housing for the rest of the camera. So, I scoured ebay for another broken S500 with a working LCD screen.
A good ebay search for this is "Casio Exilim S500 Spares or Repairs". There weren't really any, so I searched models which (with a little examination) were known to use the same screen. I bid on, and won a Casio Exilim S600 which was very battered, and had a broken focussing mechanism. Good screen though!
As soon as it arrived, I turned it on to check the screen, and then set upon taking it to pieces to get the screen out.
The steps involved in this are, from memory:
1. Unscrew all the tiny screws at the bottom, the one connected to the strap, and the one on the opposite side from the strap.
2. Pop the back plate off. Careful of that screen!
3. Use a screwdriver to prize the LCD/Backlight housing off the inside metal plate which covers the back of the camera. Use a very slim screwdriver or something very flat - it's strong adhesive and it bends quite worryingly.
4. Flip the camera over and carefully remove the front plate on the lens side. The camera is now sort of bendy in the middle.
5. Locate the backlight power cables (one black, one white) and de-solder them from the board.
6. Pull the black and white cables through to the other side and move the screen aside.
You should now have something a bit like this (actually I took the screen alone off in this photo but you are best removing the entire housing):
Step 1: Removing the battery compartment.
It needs to come off.
See the tiny screw?
It's smaller than you could ever imagine. There's a pretty duff photo of it below too, compared to one of the other screws (which are also quite small!)
Unscrew it carefully. When it comes undone the grey plastic module will just fall off.