If you like chatting with your friends on Facebook but have a bunch of other things to simultaneously do, you should probably get offline. Or use the Facebook Messenger app.
The Windows app for Facebook Messenger will allow you to use the app like AIM or MSN Messenger, except it will sync all your Facebook contacts when you log online.
It’s pretty much the same experience as chatting within Facebook.com.
It’s also kind of ugly.
In addition to allowing you to chat, the app will alert you of regular Facebook notifications, such as new comments, wall posts, or tagged photos.
You can only install this app on Windows 7 at the moment. There’s no official word on a Mac version yet.