Microsoft last week announced a deal to acquire live-streaming startup Beam. It plans to use Beam’s interactive technology to enhance the Xbox Live experience. Beam has attracted a number of top investors, including Techstars, Courtside Ventures and Ore Ventures. The deal is designed to help make Xbox Live more social and fun for users, Microsoft said, allowing members of the community not only to just watch players engage in new gaming experiences, but also to engage directly with each other.