the wellknown "create primitive transform manipulator" could be very usefull when one has to place geometrie wich has to aim at certain points of other geometry.
As much as i know until now i have to find out the delta transform values via measuring and then type the transform values into the fields of information window.
Think of the arms of table lamps, wich have to be snapped to the center of one hinge and then rotated to aim at the center of the next hinge...
