Use callbacks to create an "online" monitoring tool.
Written by Jan Jorgensen
Well, it's been a while since I started this jQuery fundamentals series, but I hope you haven't forgotten about it. If you have, please read up (parts I, II, and III) because this time, I'll put a lot of functionality into the script. This tip contains all the elements of a "real" web application, so it's important that you know your way around.