This is a really handy module for me. https://drupal.org/project/menu_token
what this allows me to do is use tokens in menu URLs. What this means is that I can create a simple URL that references content dynamically. and since it is a menu, I can easily place it with panels.
so, I have a URL whose relative path is
node/[node:nid]/edit
I place this on the node view variant page for my specific content type and I now have a movable link that will edit whatever node I am looking at. one link will allow me to edit any node.
the tabs from drupal will allow you to do this of course, but I hate the tabs because they always interfere with my CSS and I use Tab Tamer to hide them. But, I still need the functionality. and with this solution, i can style it pretty easily with css.