At my shop workstations, I like to use swing-arm lamps for adjustable task lighting. For convenience, I mount the lamp on a wooden arm that swings out from a nearby wall. Sometimes, a single arm does the trick, but when I need more reach and flexibility, I create an articulated arm by adding extensions as shown.
Make the primary arm from 11⁄4"-thick hardwood about 5" wide, tapering out to 11⁄2" at the end. Mine is 26" long, but suit yourself. Drill a 3⁄8"-diameter hole through the wide end on the drill press, using a long bit. Bore as deep as your drill press allows, and then raise the table to complete the hole. Rout or sand a bullnose onto the wide end. You can drill a hole on the narrow end to carry a lamp, or add an extension or two. Make an extension 11⁄4" thick by 11⁄2" wide and attach it to its mating arm with a 3⁄8" carriage bolt, a washer, a lock washer, and a nylon nut or a pair of nuts jammed against each other. Tighten the hardware enough to provide both friction and adjustability. Mount two metal L-brackets to the primary arm, using a length of 3⁄8" threaded rod secured at each end with a pair of jam nuts, and then screw the brackets to a wall stud.