I found this in a local forum, thought I would pas it on.
A way to warm the meat is to use the Tom Hatton lettuce method. Rinse and shake off excess water from leaves of lettuce. Put a layer of them in a pan and place the brisket (preferably sliced)(or other kinds of meat) on the bed of lettuce. Place another layer of lettuce over the meat and cover the pan with foil. The moisture on and in the lettuce will keep the meat moist while it is heated. I do this all the time and it works beautifully. I use either romaine or head lettuce. I think Tom preferrs the romain.