Using Subversion on the command-line, it intelligently tab-completes available subcommands, etc:
$ svn c<tab> cat checkout cl co copy changelist ci cleanup commit cp
Mercurial, on the other hand, doesn't seem to have tab-completion, at least out of the box:
$ hg c<tab> [nothing happens]
Is Bash completion for Mercurial available at all? What's the simplest way to get it working? I'm on Ubuntu 11.04.