I've got a few laptop users who VPN into our network from remote locations. They also have a few network drives mapped. When they are not on VPN, the network drives are disconnected, and the machines are utterly slow, almost unbareable to use. And I believe it is because they are looking for the network drives, and attempting to reconnect. As soon as I manually removed those drives, the machine regained significant performance.
Now how is one to setup a machine properly with network drives that won't always be connected?