While office hours remain the primary means through which we interact with students outside of the classroom, they are not without problems. Hours that are convenient for a faculty member are inevitably inconvenient to large numbers of students. Meetings and other conflicts inevitably cause cancellation of at least some office hours, and many faculty complain that students don't come even when they are there. The telephone and voice mail provide a partial solution to these problems. but do not free the professor from the tyranny of sitting in a particular place at particular time. A set of electronic tools, including instant messaging, e-mail , computer conferences, and collaborative composition spaces, provide variations of telepresence that allow new ways for professors to be available to students. The real time telepresence indicators of instant messaging allow professors to conduct scheduled and unscheduled office hours from any computer (home, work, library, classroom, etc). The asynchronous telepresence of e-mail, computer conferences, and collaborative composition spaces provide additional opportunities for on-line support of students. This presentation overviews the contributions each of these technologies make to a practical online office.