Tagbar is a vim plugin for browsing the tags of source code files. It provides a sidebar that displays the ctags-generated tags of the current file, ordered by their scope. This means that for example methods in C++ are displayed under the class they are defined in.
Extract the archive or clone the repository into a directory in your 'runtimepath' or use pathogen. Don't forget to run :helptags so you can access the documentation with :help tagbar.
Note: Vim versions < 7.0.167 have a bug that prevents Tagbar from working. If you are affected by this use this alternate Tagbar download instead: zip. It is on par with version 2.2 but probably won't be updated after that.
If the ctags executable is not installed in one of the directories in your $PATH environment variable you have to set the g:tagbar_ctags_bin variable, see the documentation for more info.
Put something like the following into your ~/.vimrc:
nmap <F8> :TagbarToggle<CR>
Jan Larres <email@example.com>
You can also clone the project with Git by running:
$ git clone git://github.com/majutsushi/tagbar