Whenever I create a website, I always make a mistake when choosing directory names. For example, I choose the name "wp" for my directory that houses my wordpress install, and I make my blog URL reflect that. When it comes time to try a different blog system (textpattern or MT) Now I'm stuck with the "wp" name.
It all goes back to the old lesson that nobody cares about the implementation. Name things by their name. Names are inherently levels of indirection, so encoding information about what backs the name into the name itself, is just a bad idea.
Along those lines, I've change the URL for my blog, hopefully for the last time. This blog is now http://levelsofdetail.kendeeter.com. I'm going to write about keyboards and health issues in separate blogs (since MT allows me to do so easily). They'll probably be something along the lines of health.kendeeter.com and keyboards.kendeeter.com, until I think of more clever names.
With such a naming scheme, now I can use the dreamhost control panel to point my blogs at any directory I want, and at any time I want, without breaking people's links or bookmarks. It's so obvious, and yet I seem to mess it up every time.