Assign yourself a status
It would be nice to assign yourself a status like away from my desk, out to lunch, do not disturb or maybe even leave an area to write in your own status.
Currently you have two ways to describe whether someone is present on the Speak system-Active and Away. You should have three ways to describe someone's presence in Speak-Active, Inactive(logged in but not active), and Away. Just because someone hasn't "touched" speak shouldn't make them Away.