I have time & again read/heard that the one thing that seperates a guy with an athletic build and a guy who weightlifts are the size of the traps. Supposedly there are no natural things we do that can increase the size of your traps. Don't know if that's true or not but I work on them anyway.
My Shoulder & Trap Day Routine
~Seated Barbell Shoulder Press
~Front/Lateral DB Raises (P90X style)
~Bent-Over Reverse Flyes
~Upright DB Rows
~Barbell Shrugs (heavy)
~Seated DB Shrugs (heavy)
~Tea Cups (using dumbbells you raise your arms in from of you high and use the dumbbells in a motion like you're pouring a cup of tea).
Do you specifically work your traps?