I could just compress the directory as a .zip file w/ a password (which I think would just look like a compressed folder w/ a password) but I'd like something with less overhead (i.e., none of the decompression, etc.)

Any ideas?

Clarification/update: I'd like to have anyone be able to access it from another computer if they know the password. I.e., I don't want them to have to log in as a different user, etc., but, rather just enter a password.