Previously we had covered a desktop tool based on Adobe Air, which allows you to upload photos to Facebook. If you are looking for a tool for providing desktop notifications about your Facebook activity, then Notification is a good tool. Notifications is a .NET based application that notifies you of new Facebook messages, events, friend requests, etc on your desktop. The application sits in the system tray and provides notifications with sounds for new messages, events etc.
Desktop notifications from Notifications.
You can also compose a new message to your friends from this application.
This tool should be a pretty useful one for people who use Facebook more and gets too many notifications daily.
Download Notifications
thats a very useful tool, i use the facebook sidebar gadget for this, but it aint that good. This is much better.
If you need a desktop client to chat with facebook users check this out.
http://alfred.co.in/software/facebook-instant-messenger-im-use-facebook-chat-outside-facebook/