I've adapted Heston Blumenthol and Thomas Kellers approach to poultry brining.  It's simple basic brine that will make you bird ultra tasty and moist. The aromatics used are completely up to you. Experiment with chili, lemon grass, star anise and coriander seeds for an Asian style brine.

15g of table salt per kg of Bird
3 tablespoons honey
5 bay leaves
1 head of garlic, smashed but not peeled
1 tablespoons black peppercorns
2 star anise
3 large rosemary sprigs
1 small bunch of thyme
1 small bunch of parsley
2 lemons halved

Weigh the bird and calculate the about of salt you will need.  In a sauce pot, combine 3 pints of water and the salt, the honey, bay leaves, garlic, peppercorns, rosemary, thyme, star anise, parsley and lemons zest. Bring to a simmer over moderate heat, stirring until the salt is dissolved. Let cool completely.  Add the chicken to a pan that will comfortable hold them. Add the brine base, then top up with fresh cold water until the chicken is submerged. Brine for at least 12 hours for chicken.

Remove from brine, rinse and remove any aromatics that may stick to the bird. Pat dry and roast as usual.

Variation for Turkey:
Double the quantity of all the aromatics. Use oranges instead of lemons. Add a couple of cinnamon sticks and few table spoons of fennel seeds.

With turkey you can brine for up to 24 hours.