The company that gave us the BlackBerry – still the dominant phone in corporate circles – thinks its business customers will have room in their briefcases for at least one more device: the PlayBook.

Research in Motion Ltd. showed off the tablet for the first time Monday and is set to launch it early 2011, with an international rollout later in the year. With it RIM is betting on a smaller, lighter device than Apple Inc.’s iPad, which kicked-started the tablet market when it launched in April.