Re: waste of time
I'm afraid I'm going to disagree that it's a waste of time - certainly for larger projects.
At work we use CC.NET as our build system, and I'm not sure I could survive without it.
One of the biggest advantages for me is that, while I'm working on some low-level bit of the project, I don't need to bother checking out and building the huge amounts of dependent code that sits on top of my component. Instead, every now and again, I grab a build from the build server, unzip it locally, and run with that.
Sure, I could grab all the source from the SCCS, and end up with a huge solution in Visual Studio, but there's no need.
It also makes life far simpler for the testers: they don't need to spend time configuring the build on their machines, they just grab a build from the CI server.
Another advantage is as a "point of reference" for bug reports. If someone raises a bug, they have a definite build number, which greatly simplifies tracking down the problem. When the bug is fixed, it's resolved as "Fixed post build xyz", and the testers can know when to expect that fix to be in place.
As for CC being hard to configure, I haven't had to work with that side of things. I'm thankful to our build manager for handling that for us!
Rob