I really like the rack and pinion setup, as for the lid, there will need to be a lock that can be opened and unopened for that to work.
But before things go off on a tangent (more so myself doing this), an idea that I had heard today was VOX, more specifically using it as a method for the toolbox to recognize general terms like, "screwdriver" or a number assosiated to a drawer... and thus forth opening that specific part of the box.
The stampy algo is a good base to look at but when we get down to things it needs to be very advanced... that's what the project is supposed to be. So in having, pretty much, a small single board computer the options are endless.
So any "need to have" or "enviable" features that you may have in mind?