A universal login using vB data

[Vigile]

I am looking to see if anyone can help me with a problem I have been having for over a year now -- how to let the 96k+ registered users on our forums use their existing vb login information on our entire site.

We are doing site expansin with a lot of interactivity and we need a universal login system that would allow them to visit various sections of the site and the forums without having to have BOTH a vB login and another one.

I know that if the sites are on the same severs you can simply include the global.php file check for the $bbuserinfo[userid] and then base the sites output on that result. However, the forums and main sites are on DIFFERENT servers and as far I can tell, there is no way to "include" the global.php files from another server on a PHP script.

I have also thought about simply checking for the vBulletin cookie on the users system for the scripts on our main site -- this is a simple "does it exist" type of query and seems to work, but I worry about the security of it. Would it be simple for people to simply "spoof" cookies to login as other users? that kind of thing.

Surely there must be some way to do this...? Any help would be greatly appreciated!

Bump for any assistance. I asked for some simple ideas from the VB staff in the official members area and they refused sending me here again.