One of my fav ones is that you can give a network adapter a "fallback" IP address and gateway, but still keep DHCP enabled

I wish MS would "borrow" the feature in Mac OS where you can set up different networking profiles, including proxy settings that programs can tap into. To change your location, you simply hit the Apple Menu, choose Location, then the location you are at. There is supposidly a way to have it switch automaticially based on the network connection as well, but I haven't worked with that.