I don't want to access the DB table directly, even it is more easier to write the extension. But access to DB directly will make the extension strongly related to the Forum's version. Actually I am not familier with the module develop, I just go through tutorials found of the forum. Most of the program I wrote is about the window steamming media and using DirectShow and DirectShound. In windows application, I negotiate with other module through the standard interface so most module can work fine even the core framework upgrade. I just with a few experience with the DNN module, but I feel it would not to hard to me if I just write some extension of the forum.

What I want to write is some extension of other solution has but not found it the DNN world, for example, the Tag module or others. I will reference the module of Xoops, phpBB's, and Discuz's extensions and try to implement a similar function to DNN forum if possible.

Just for example, in the DNNForums, the top thread show

The most popular thread has been Re: Search by Author does not seem to work?
The most active thread has been Is Vista Theme available to use?

but both links will links to Search by Author does not seem to work.
I can't link to Vista Theme available to use in the top thread.