Set your smoker up to cook at around 300F. I bet, if you were careful enough, you could do this on a weber kettle but it's easier in a smoker.

Trim your brisket if needed. Please, please, please leave at least 1/4 inch of fat minimum on it. Fat tastes good. Trust in Julia Child. Her words, not mine.

Season your brisket liberally with Aaron Franklin's secret rub. Smoke the brisket fat cap up for 4 hours. At this point check the internal temperature. It should be somewhere around 160-170F. At this point wrap your brisket in butchers paper and continue to cook fat cap down until you get to an internal temperature of 195-200. This is another hour or two max. You are looking for probe tender.

Pull the brisket and let it rest for 30-60 minutes (or put it into a pre-heated cooler if you need it to stay hot longer). Slice against the grain. If you blow it you can always serve it with BBQ sauce but if you nail it you will not want to do that...

Google it for details but a lot of BBQ forums talk about the faux cambro. This is an easy way to keep your BBQ brisket hot if your timing doesn't quite work out. All you do is take a cooler a bit larger than what you are trying to keep warm and pre-heat it by filling it with hot water. You wrap your meat so it doesn't leak and fill the empty gaps around the meat in towels. Make sure you don't use nice towels. Try as I might I always have leaks... BBQ scented towels. Is that really a bad thing?