When you grade a student's assignment, you can type comments in double brackets. In the application itself, it says the comments will appear to the student in red. However, in the project site I am working on right now [Honkytonk Heroes] I have different usernames, two as "access" and me as "maintain". When I graded the assignment and looked at it as the student, the commented text was underlined, not in red.
(orignally from Vanessa Richards)