This is a Lokka plugin to add "Hatena Bookmark Button" link.
Run these commands:
$ cd public/plugin
$ git clone git://github.com/nkmrshn/lokka-hatena_bookmark_button.git
$ rm -rf lokka-hatena_bookmark_button/.git
You can set options in the admin page [Plugins]->[Hatena Bookmark Button].
The helper method is "hatena_bookmark_button". Don't forget to modify the theme template. This helper method has two parameters. First is for title and second is URL. If the hatena_bookmark_button method called without URL, current page URL will be used. If you want to specify the URL, call the method with String parameter like:
<%= hatena_bookmark_button(@entry.title, "http://example.com/foo/bar/") %>