Multiple Domains?

I have two consulants that have laptops. The laptops are running windows 2000 prof. they need to be able to access two different domains. I have 2 network cards in the laptop one for each domain. it seems to work. the problem in question is when they are logged into the “a” domain and save there documents, and then they travel and log into the “B” domain how do they access those documents. They are setup as restricted users so they can’t break anything. I was curious if anyone had any experiance with this. If anyone has any imput I would greatly appreciate it. Thanks