Is there a way to pull this information up ? A search that can be performed ?
Just something to list all topics that have been started and or replied to in the last 24 hours.
On the search page just have it search everything, that is within 0 and 1 days old?
There is a link, that is at the top in the default theme, that you can click on called "Show unread posts since last visit", would that work better for what you are trying to do?
What are you wanting it for?