DIY Book Scanner

Basically i need an affordable Canon compact camera which is supported by CHDK and also has the battery/sd slot on the side. The reason for this is that my tripod has a wide base to support the camera so it's impossible to have the camera mounted and also use those dc couplers to make it run off mains power. Also, the usb port must be on the side too for the same reasons.

So any cameras that can possibly be connected to mains power and usb remote trigger while mounted on a big tripod?

Think most can. I have the PowerShot A810 and on that the USB port is on the right side of the camera and the opening for the power supply is on the same side even though the battery compartment opens at the bottom.