https://github.com/pidu/goto-gem.git
git clone 'git://github.com/pidu/goto-gem.git'
Open an installed gem in dired
Installation alternatives:
load-path.package-install.Issue M-x goto-gem to open gem directory with dired.
Issue M-x goto-gem-grep-gem to run rgrep within an installed gems directory.
Issue M-x goto-gem-grep-all-gems to run rgrep over all installed gems (possibly quite heavy weight).