A Web security company is offering a free tool designed to prevent users of social networks from posting embarrassing drunken messages online.

On the premise that \”Nothing good happens after 1:00 am,\” the tool from Colorado-based Webroot promises to \”put an end to the embarrassment that follows regrettable, late-night posts.\”

The \”Social Media Sobriety Test\” is a free plug-in for Firefox Web browsers.

It requires a user of Facebook, Myspace, Twitter, Flickr, YouTube or Tumblr to perform a coordination test before being allowed to access the service.

The tests include keeping a cursor inside a moving circle or correctly identifying a series of flashing lights.

If a user fails they will be blocked from using a service.

Sobriety Test users can set the hours they would like the blocking tool to be in force.

Google also offers a tool for its Gmail service designed to prevent users from sending drunken emails. \”Mail Goggles\” forces users to solve five simple math problems in less than a minute in order to send a Gmail missive.