Here's a module or feature for drupal core I hope would be simple to make if anyone is up to it:

http://universaleditbutton.org/Universal_Edit_Button

Here is the actual html tag you need to output to signify a page is editable:
http://universaleditbutton.org/Add_The_Link

Comments

Quirky... I like it! You're

Quirky... I like it!

You're right, it would be fairly simple.
As far as I can tell, just use http://api.drupal.org/api/function/drupal_set_html_head/6 in http://api.drupal.org/api/function/hook_init/6
Then you'd need to check you're looking at a node and the user has edit rights...

Module available

Module available now at http://drupal.org/project/admin_links