using unix improved!
Starting with the 2007-2008 school year, all cs accounts will by default have their email forwarded to their ITS account (if you have one). So you shouldn't have to worry about running email programs on the CS machines. Just use Swatmail, and anything your CS Professors send to your CS account will get forwarded.
If your CS email isn't being forwarded, just create your own .forward file. Here's one way to do it (type this in at the command line, changing jdoe1 to your ITS username):
echo jdoe1@swarthmore.edu > ~/.forward
If you want to stop mail from your CS address being forwarded, just remove your .forward file (rm ~/.forward).
If you want to *send* email from your cs account, you can use either pine or mutt (first you'll need to know how to use an editor, like emacs or vi). Both are fairly easy to use -- just start them and follow the on-screen menus.