[Scott-28] recently sent in a particularly well-documented project that turned an antique rotary phone into a digital kitchen timer using an internal Arduino ... seven-segment LED display to ...

This hack was built for [Hlesliebole]’s Nikon D3100, but he says it should work with any DSLR and remote shutter. This initial build uses an LED as a stand-in for the remote shutter that he ordered.