I’ve already written about a service, which website users can make use of to keep track of visitors currently online on their blog / sites.
If you are a WordPress user, then along with who’s amung us, you can also use UserOnline plugin by Lester ‘GaMerZ’ Chan . With the help of this plugin you can display how many users are online on your WordPress blog with detailed statistics of where they are and who there are(Members/Guests/Search Bots).