Is that you must deny phyical access.
http://en.wikipedia.org/wiki/Computer_insecurity#Direct_access_attacks
Sadly, given physical access, there is little you can do.
Bob
I rent a room in a house for 3 and I always get this feeling that someone is snooping around my external HD by plugging the HD into their laptop when I am not home.
How can i password protect the HD or show only certain files? Encrypting a 250 gig HD sounds like it takes forever so perhaps it is not a considered option?

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