BSTray 4 OS X
BSTray 4 OS X is a free open source Mac OS X Cocoa/Java application which provides audio and visual Dock alerts from a Big Sister Display server on a Mac OS X system. Its a simple system that checks a webpage at defined intervals using a regular expression to see whether any alert images are shown on the Big Sister monitor webpage. Also supports basic http authenication. It could easily be adapted to look for any web based content and provide alerts in the OS X dock. Uses XCode and the Cocoa Java bridge, I wrote this really just to learn a bit about coding on Mac OS X. The source code and binaries are provided completely free of charge and are in the public domain, although if you make any changes of use to others, i encourage you to let me know, so we can make them available to the community.

Copy bstray to your application folder. When you first run the application use the menu to edit bstray.ini to add your Big Sister Display server, remove the password section if you do not have http basic authenication on your Big Sister Display server, then restart BSTray4OSX. You can then add bstray to the startup items via System Preferences.

For the Big Sister server and the Windows version of BSTray see http://bigsister.graeff.com

Please note this application and source code is provided free of charge and totally as is and without any sort of warrenty at all. If you use this software, you do so at your own risk.
BSTray4OSX Binaries:

BSTray4OSX Source (XCode project):