In every screen (entrygroup) where you can add javascript (<script>) into the custom content box you can reference the clientside CurrentUser object.  You can see that this has been used in several articles in the blogs such as "Controlling Buttons using Client Side code

And other articles discuss how the CurrentUser object could be used to extend the functionality further by making reference to the current users team or checking whether the user has info manager permissions. (See:  How do I hide the 'Follow-up' check boxes on a New Appointment or New Task Screen Screen?)

If you add the following code into the custom contentbox of a screen e.g. CompanyBoxLong you will see all the information to you that can be accessed in clientside script.

var strOut = "<ul>"
var x;
for (x in CurrentUser)
strOut+="<li>"+ x+"</li>";
strOut += "</ul>"