Robocopy (from Microsoft Windows Resource Kit) is really a must have tool to copy files accross the network.
But it's a command line and has so many options that every time I use it I must open the documentation to remember witch switch to use.
Thanks to Derk A. Benisch and his team there is a great GUI wrapper that save me a lot a time.
More info and download at www.gotdotnet.com/codegallery