I have found that a modelling tool (such as Sparx Enterprise Architect or Archi) as opposed to a drawing tool is useful.
With a modelling tool there are increased opportunities for reuse and for the information to be presented in different ways (with differing levels of detail) depending on what needs to be communicated.
It's not ideal, but I do however often still use both Visio and Powerpoint to better communicate the information in a more visual manner.