Set up grill for indirect cooking (no heat source directly under bird) over medium heat. Stabilize the heat around 325°F.
For the rub: Combine salt, brown sugar, coriander, pepper, and zest; set aside until ready to use.
Remove neck and giblets from chicken cavity and trim off any excess fat. Rinse the bird inside and out with cold water and pat dry with paper towels. Then lightly coat the chicken with the oil and rub chicken generously inside and out with spice mixture. Let chicken sit for 30 minutes to allow the rub to cure.
Here's the fun part... Open a beer and drink it, then open another and drink or drain half of the can. Squeeze the lemon juice into the can and set the can in the "cup holder" of the vertical roaster. Slide the chicken over the beer can and you're ready to go. (If you are not using the vertical roaster, set the chicken over the can so that the legs and can form a tripod. Carefully place beer can and chicken on grill over drip pan.) If you are going to cook the potatoes as well, toss them with a little oil and seasoning and scatter them around the bottom of the roaster in a single layer.
Close the grill cover and cook 1¼ to 1½ hours or until internal temperature of the breast meat is 160°F and the thigh meat registers 175°F. Carryover cooking will raise the temperature another 5°F to 10°F.
Remove from grill and let sit for 10 minutes. Carefully slip beer can out of chicken and carve.
Serve hot with lemon wedges.
Recipe by Grilling Outdoor Recipes powered by Bull Outdoor Products at http://www.grillingoutdoorrecipes.com/coriander-and-black-pepper-beer-can-chicken/