An inexpensive nylon-bristle brush and a few small "acid" brushes that are sold for applying soldering flux can make great tools for spreading glue. Clipping off about half the paint brush bristles will make them stiff enough so they won't slop glue around on board edges or mitered joints.
You can attach a length of soft copper tubing to extend the reach of a blow gun nozzle used with an air compressor. The extra length will allow you to clean out motors and interior machine parts without getting a face full of dust. The end of the tubing can be bent to reach around the back side of motors or into other hard-to-reach areas. Use a wet/dry vac along with the blow gun to help keep dust out of the shop.