[HM666]

That will depend on what you want to do exactly. Some bridges only link member accounts and give you one login where as I know in the past some have allowed members to also post in both Wordpress & vBulletin although I'm not sure of the likelihood of that being the case as of late. There are a couple of them out there.

There is this one: http://vbsocial.com/wordpress-vbulletin-bridge/ This one I have tried in the past. It seemed to work pretty good although I do remember a bug or two, but I do not remember what the problem was off the top of my head. I also remember that they were pretty easy to fix though so that is actually a good thing in the long run. The support over there is pretty good. If you go this route and get the VIP membership keep in mind that its reoccurring.

Then this one: http://codecanyon.net/item/vbulletin-connector/4126499 I've never tried it, but it looks pretty good, you would have to read it and read the comments to see if its what you would need.

Then there is this one: https://vborg.vbsupport.ru/showthread.php?t=270517 I also have not tried this one either.