Keeping two computers on the same network in sync

My wife has her own MacBook, as well as an account on our shared iMac. I want to know if there is a way to keep her accounts on both computers in sync. This way she can access all of her files on either computer, and changes made to any files on one computer would automatically propagate to the other.

Hmm...well, how many files? Easiest may be just to do Dropbox to sync between machines.

Use Dropbox.

I'm talking about keeping the entire user account in sync, not just a few files. Also, isn't dropbox internet based? I want something that will work over the local network, instead of the internet.