If you like, you can store your files on your local hard drive instead of on Athena. The advantage of this is that you do not have to rely on AFS servers working or be limited by your Athena quota. On the other hand, you will have to copy all of your files from your locker to your hard drive. You will then have to telnet to your machine anytime you want to access those files.
If you choose to keep a local home directory, note that many programs have configuration files stored in your home directory. For example, discuss creates a dotfile called ``.meetings'' in your home directory, and updates it each time you use discuss. These files will not be in sync with the ones in your Athena home directory. Keeping these in sync can be annoying. One technique is to symbolically link the files from your local home directory to your Athena home directory.
Another alternative is to export some local files via NFS. This
approach makes the export more transparent, but has one major problem:
NFS is not secure, and we recommend that you do not run an NFS
server. If you really, really want to export files via NFS,
however, there is a way to make NFS relatively secure: Make sure all
lines in /etc/exports are of the form
/usr/export *.mit.edu(root_squash,ro)
where /usr/export is the root of a tree you want to make
publicly available.
The *.mit.edu restricts access to machines in the mit.edu domain, the root_squash remaps root to nobody and the ro makes the export read-only. Read the exports man page for more info. Be aware that using NFS at all can open up security holes; it is entirely conceivable that anyone could read any file on your system. (This may be a little paranoid, but you're much better off being too paranoid with NFS).
In general, it is probably easier (and safer!) just to use your Athena home directory.