A few weeks ago, I launched a new utility called DrupalVersion.com. It has one simple purpose: find out if your sites are up to date with the latest version of Drupal (6 or 7).
As a site developer for a web development agency, I often have the need to send clients pieces of content (pages, blog posts, team bios, etc) for review. These are pieces that cannot yet be live in the site, so they need to remain unpublished and be reviewed.
Sending links to clients with a login string in the URL is a great way to speed up the process, but I had to write a module to iron out the wrinkles for our clients.