Really handy RVM hook to symlink current gem directory

I use gedit to write code. I keep a filebrowser tab open at the left side of my screen,
and sometimes I need to look at gem's source code.
RVM is awesome, and it keeps my 1.8.7 gems, 1.9.2 gems and all my gemsets separated,
but this makes it tricky to find the gem you need to look at.

Enter RVM hooks! If you want a symlink to the current gem directory to be updated each time you switch ruby versions,
save something like the following code to ~/.rvm/hooks/after_use

ln -nfs $rvm_ruby_gem_home/gems ~/src/gems/current_bundle

Now you have access to the source code of gems from the file browser in your editor.