Several forums - one memberbase

I am working on this very same issue right now. I plan to set up another forum, and I want it to share the same user base. I have a future plan for a site to use the same topic table, etc.

What I am doing is this...Instead of custom coding each page, I am in the process of stripping out the use of strDbTable variable. I am replacing the strDBTable  prefix, and updating it to hold the actual table name. I am doing the same for stored procedures. These table name s are then stored in a config file. This way I can have two forums set up, and tell each to hit MainAuthor as the author table.

Admittedly this is taking a lot of changes to the code, which prevents me from ever upgrading, and I have to make changes in the SP's, but that's OK with me, as I am also converting much of the embedded SQL to SP's anyway.