Desktop messenger wanted for Palkey

Hi, I need a desktop messenger like yahoo, msn and google talk for this site palkey.com. It shd do the following :- 1) Show an alert popup whenever there is a new listing added and matches the listing filters setup by the user separately into his palkey account. 2) The alert popup should contain the listing main picture and 5 other fields from the listing. 3) The alert popup should minimize after showing up for 2 seconds (something like gmail desktop notifications). 4) After the popup is minimized the messenger icon which is active at the bottom right hand corner of the desktop should show the total new listings. 5) When the user double clicks the messenger icon and maximize it, all the latest listings should be listed in a vertical table. The listing will contain the main picture and 5 other fields. When the listing is clicked it should open up the respective listing on palkey in a browser. 6) After the messenger icon is maximized for once the new listings count should reset to 0, so any new listings after that will be counted from 1 again. 7) The messenger will auto load whenever the system is started and shown as an icon at the desktop tray at the bottom right. 8) The software installation should be simple and SHOULD NOT require any pre-requisite installations like MS dot net platform.