You should make it so users can change the order that
messages are listed in their folders. For instance, I
prefer to have the oldest messages in my In-Box at the
top of the list and the more recent ones at the bottom.
That way I know which e-mails have been around the
longest and need to be answered sooner. Furthermore,
many e-mails I receive are from list-serves and are
subsequently repsonses to earlier messages, if I could
change the order my messages are listed I would not
have to read a message, go to view previous, then back
to the first to delete it, then view previous again,
etc., etc. This has been a huge complaint from a
number of my fellow students about the webmail service.