Real time Protocol for a web-app in PHP

[psd-plus]

I'm working on a PHP application and I'm looking for some ideas for a real-time protocol that I can use for:1) track users status and location within the application (this should be fast!!!)2) chat system.I'm looking for something like FMS and its "Shared Objects" where multiple users can subscribe to pieces of information. FMS is expensive and slow for what I need, I would need a widget loaded on each page, requesting a new connection to the FMS server, etc.... slow...I need something fast, ope source would be perfect!. Something like what Google Waves uses for syncing shared documents.Any suggestions?