I use named branches in Mercurial.
In doing so I have created one branch called playground where I can try out various wacky experiments. I never intend to merge this b
Mercurial 2.1 introduced the hg phase
command which allows users to control what change sets are exchanged with remote repositories. @MartinGeisler answer to this question details this method.
If you want to create a local branch of your code you have a couple options. You can hg clone
the repository which will locally create a branch of the entire repository in your filesystem. The other alternative is you can try to use a Mercurial extension like LocalbranchExtension.
There are many ways to branch in Mercurial without using a named branch. Just find a method that suits your needs.
Further reading: http://stevelosh.com/blog/2009/08/a-guide-to-branching-in-mercurial/