When you view detail of a Document Library file in SO, which has many (100+) versions, often an JS error is raised, saying that "Script runs very slowly on this page".
(1) Go to Document Library.
(2) Upload new file.
(3) Create many revisions of the file (100+).
(4) Scroll down in the list of versions.
Toolbar is not shown for very long time, eventually JS "script runs slowly on this page" is shown. Overall very slow response in IE7 and Vista, sometimes it's necessary to kill the browser using OS tools (e.g. after 20 minutes of waiting and browser being not responsive).