I have Dell Latitude D600 laptop, which I use for lot of my work, and it works fine for 90% of what I need. One really annoying thing though, is that in many places I need to use static IPs. Now, problem is, that it meanns I have to manually reconfigure network settings for each place. So far the only workaround I found is to detect docking station/port replicator presense and configure accordingly. Unfortunately there is no information on how to do that propperly. Best I was able to do is to check if USB root hub is hanging off of USB bus. When docked foloowing line appears in lsusb output:
Bus 001 Device 002: ID 413c:0058 Dell Computer Corp.