Would the Rogue Trader be involved in the Cold Trade (selling xenos artifacts to nobles with more money than sense)? If so, we take a little trip into the Screaming Vortex pick up a bunch of chaos tainted weird things, and sell them on. No idea what they do, but it will be fun seeing what happens (from orbit ;) )<br/><br/>The Calixis sector I don't think is located in the same segmentum as the Tau, but I expect there are other xenos races could be made use of.