My Linux box was hosting Subversion with no problem. I added a new repository to the several that were already present, and when I checked it out, it said, "301 Moved Permanently". Excuse me?
As it turns out, there is a 301 error section in the Subversion FAQs. It says that this typically means your Apache configuration is invalid (nope, the rest of my repositories worked just fine) or your repository has the same path as a literal directory on your web root. Ahhh!
Sure enough, my subversion path was http://myserver.com/xyz/, and I had a literal directory named "xyz" in the web root. I changed that directory name, and Subversion would then allow me to checkout the repository with no problem.
