Felix Stahlberg's plugins:
This PlugIn integrates a modified version of PhpFreeChat. Pfc is a fast, customizable and multi languages ajax chat with a wide varity of features. The plugin provides several customizations via the tool administration page.
Use the PhpFreechat in you're Elgg installation.
This plugin works with Elgg 1.2. For older versions please visit the project homepage.
I had some Ideas to make your great plugin even better. Could you create additional profile menu item to invite the user to the chat and some kind of notification on the topbar (like new messages and friend-request) when invited?
It would be great if you can do it some day : )