I am interested in miniature motors and power transmission devices (lead screws, nuts, etc) which can be used in small autofocus camera designs. The motors can be servo (with encoder) or stepper. The leadscrew size is about 2 mm.
There is a new (at least to me) motor out there called Squiggle. It is really small, and looks like it has already seen application in some camera focusing applications. It can be operated closed loop or open loop from what I can tell. Check out http://www.newscaletech.com/. Cool stuff, wish I had an application!