I think a way to add a special event that occurred on a particular day to the sidebar area would be cool.
Perhaps a text file where the forum owner could enter an event for each upcoming day and have that show in the sidebar, changing of course everyday.
"On this day, in 1967, - Keith Richards, Mick Jagger & Marianne Faithful busted for drugs"
(the above is actually true for today's date)
There are websites that have information like this as well as famous births & deaths. Here is one such website with all of these: