CAMBRIDGE, MASS. — Does Xerox CTO Sophie Vandebroek have trouble with basic numberwork? At MIT's EmTech conference, she asked the audience how many people had "avatars" — digital characters for virtual worlds like Linden Lab's Second Life. From what I saw, half a dozen people out of some 300 attendees raised their hands. "Perhaps 25 percent!" she said, as she played a video showing off Xerox's presence in Second Life. I am not sure what is more disturbing: Vandebroek's miscounting, which one might blame on the bright stage lights, or her inability to calculate the lack of a return on investment in Second Life, which has no such excuse. Here's a clip of Vandebroek talking in Second Life: