Call for Help: Share and protect files on a home network?

Reader Adam writes:

I just bought a new laptop, and I'm looking for a way of sharing everything between my desktop and my laptop on my wireless home network, without letting the prying eyes of my housemates into all of my private files. Is there a way of creating a private network between my two computers that's just for me?

My first instinct would be to recommend trying out something like Hamachi, but having never done this myself, I'd love to hear what ideas our crafty readers have. Let's hear how you'd handle Adam's situation in the comments or at tips at