I use Blackboard/WebCT for all the courses I teach. All announcements (
assignments, exam, ...) are made on Blackboard and emailed to all
students. All handouts are provided through Blackboard electronically. I
don't distribute hard copies and I don't take any hard copy submissions. I
also post all assignment scores and cumulative total scores in Blackboard.
Hence I won't bother to remind any student. The student has no excuse to
miss any assignment or deadline. In most courses, I don't grade them based
on attendance.
If a research course requires in-class discussions and attendance/
participation is part of course grade, I make it very clear on syllabus
and
I periodically release their participation scores.