GAMES: World of Warcraft

This looks to be a good one.
see here

J2EE: More on WebSphere HTTP Session Management

This is a darn fine article on session management in WebSphere. Well worth a read and seems pretty comprehensive.

Of particular interest to me was the session back up option that allows the session to be stored in two servers. The theory being that you would lose one at a time (either through error or planned outage) and that all the sessions could be maintained through this process. Restrictions include that the session state data must be stored in serializable beans and I imagine you would get spurious errors if these beans were to change their signature and you ran two versions of these beans at the same time.

Well worth a look though.

J2EE: HTTP Sessions

Bit old but this is a good overview for non-techy's. Has WebSphere bits in but again, a bit old.