"Who's logged in" help

[eluser]spmckee[/eluser]
Greetings,

I have read several threads on the "Who's online" functionality but still can't make sense of them. I do understand the method of finding the latest, active users via the "last activity" column in the DB. What I need big help on is pulling that info out and using AJAX / Javascript for updating the information on the fly. I'm a complete noob with javascript stuff.

Are there any simple CI helpers or tutorials that can get me headed inthe right direction?

Thanks!
SP