Is there a module that shows when you last updated or modified an installed module?
AFAIK, no module, but ls -l in your module directory should give you the dates of last updates.

Btw. it is trivial to create a module that does this. Just throw a module wrapper around something like:

$modules = '/www/sites/all/modules/'; // Path to your module directory.
$output = shell_exec('ls -l ' . $modules);
echo "&lt;pre&gt;$output&lt;/pre&gt;";