What is the best way to build 50 projects (DLLs)?

These projects have many inter-dependencies.

I know how to build them in the Visual Studio WorkSpace, but I want to create a BATCH file so that I can run overnight builds.

Visual Studio HELP says you can EITHER build from the Command Line OR export a MAKEFILE and use NMAKE.

Which is the better method for my setup?

Any sample batch files would be greatly appreciated.

(P.S. An additional question if I may...My DOS is rusty - I cannot remember the line continuation character for splitting up large commands onto new lines. I have tried backslash, underscore, $_, etc, but I cannot get anything to work. Does anyone know the answer?)