We usually see personal web pages like `http://example.com/~someone/`, in this case, "someone" is a user of "example.com".

How to enable this by default, so whenever we add a new user "foo", then `http://example.com/~foo/` is created automatically? Is the tilde in "~someone" optional, customizable?

**Software environment:**

Webserver: Apache or Yaws (Erlang based webserver)