"I like to get the grill nice and hot, and cook chicken al mattone where you press the bird under a brick. First you spatchcock a whole chicken, season it, then get the skin pressed nicely onto the grill for a crisp outside. The brick flattens out the chicken so it cooks evenly before transferring it to the oven for a few minutes. If you happen to have leftovers, it's a great alternative to a regular roasted chicken and you can repurpose throughout the rest of the week."
Having cooked chicken with a brick, I can attest to its greatness. Like Guy says, the brick simultaneously flattens the chicken and causes it to sear really nicely. Just be sure to cover the brick with a few sheets of heavy-duty foil and use a thick glove to remove it from the chicken (The brick will retain a lot of heat from the grill, and you don't want to burn yourself). If you find yourself needing more inspiration, check out these recipes made with leftover chicken.