You'd need domain admin rights on the opposing Forest (assuming it's just one domain). It would probably be easiest if you were to set up an account in that domain that had the same ID and password credentials as your current one. In addition, I would think that you'd need to set up your name server as a secondary for the opposing domain, so the MMC snap-in recognizes what you're trying to administer. May I ask why you're against Terminal Server?