This is a dummy battery for the Canon IXUS/SD series of digital cameras (Battery NB-4L). This was just a test to see if my initial design would fit into the camera, after some minor sanding on the edges it fits perfectly.I plan on making some further modifications to add conductors for the battery terminals which will allow me to hook the camera up to a DC supply (there is a flap on the battery door for a cable to go through). Canon do actually sell a product that does exactly this but as you can imagine it costs a fortune. I had a quick look on eBay and the cheapest one was about two times the amount I paid for the camera.This camera and many other Canons in this series support CHDK which is custom firmware that allows you to do some cool stuff like time-lapse and remote triggering. You soon run out of juice on a single battery which is why a DC supply is essential for any kind of real hacking.This is part of a much bigger project which will follow up on Schmarty's work and involves some software mods to ReplicatorG and the Thing-O-Matic motherboard firmware.Please let me know if you have any input on how I could go about adding conductors. I think I will need to hollow out the design to allow for connections, I was thinking something like nails for the conductors, inserted into the top and then solder wires to the end of the nails.