Display current rvm gemset and git branch in your prompt (bash).

.profile

# Adapted from: http://ariejan.net/2010/04/25/ruby-version-and-gemset-in-your-bash-prompt-yes-sir
function rvm_version {
  local gemset=$(echo $GEM_HOME | awk -F'@' '{print $2}')
  [ "$gemset" != "" ] && echo "@$gemset"
}

# https://github.com/git/git/blob/master/contrib/completion/git-completion.bash
# defines '__git_ps1' current git branch function
source ~/.git-completion.bash

export PS1="\$(rvm_version) \$(__git_ps1 '(%s)') \$ "

looks like:

@olympics_2012 (feature/parse_some_xml) $

And, with colors!

function rvm_version {
  local gemset=$(echo $GEM_HOME | awk -F'@' '{print $2}')
  [ "$gemset" != "" ] && echo "@$gemset"
}

export PS1='\[\033[1;34m\]$(rvm_version)\[\033[0m\] \W$(__git_ps1 "\[\033[1;32m\](%s)\[\033[0m\]") \$ '