Instead of IPMessenger, I am still using the FREE Yahoo Messenger. I do the same as you, Adam and it freaks the patients out. We never give any patient's last name. I can message a staff to see when a patient's last colonoscopy was and then while I am moved onto something else, the staff can call, find out, request the report and message me back all within a matter of minutes. And usually the fax is also there before I am finished with the patient.
Even better, if a patient is going on and on and on about their second cousin's bunionectomy I can message the staff "GET ME OUT OF HERE!" and within seconds, there is a knock on the door telling me the ER is on the phone. Whew! I have also had to use that ploy when my second cup of coffee kicks in at a disadvantageous time.