App that checks website, rings bell if condition met

I need an app that will run in the background and do the following: Every n seconds (user selectable), the app will request a webpage and determine if a condition is met. Specifically, the app will be determining if a webpage has changed in a specific way, and I'll give you all the info you need to parse the webpage to determine the change. (Don't worry - I'll disclose the full details to winning bidder. I can already do it in PERL... it's simple.) If the condition is met, a Windows "chime" (to be determined) or maybe a small .wav file will be played. The app must be startable and stoppable anytime the user wants, but when running it needs to be completely unobtrusive. Systray? Thanks. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Installation package that will install the software (in ready-to-run condition) on the platform(s) specified in this bid request. 3) Complete ownership and distribution copyrights to all work purchased. ## Platform All Windows