Nikon and Canon DSLR’s have moved away from the 10-pin screw-in connector for shutter and general control, and have moved to a new small series of connectors. Typical of this is the Nikon N3 plug used on the D90 and D7000. Canon may be using this too. There are a number of other styles - all equally hard to find.
With the camera controls that can be created with Arduino and various parts, it would seem a natural for SPE to offer a selection of camera connectors as well as cables that would work with DSLR’s. Cables could be camera on one end - terminated in tinned leads, some in 3.5mm stereo jacks.
Also supplying bare plugs for real DIY cable-making (with details of the what the leads go) to could be useful as well.
Flash triggering can often be done via a 3.5mm mono jack - perhaps 10’ male-male leads in this area would go with the camera leads.
=Alan R.