Registration Choose Secondary Usergroup

[soundboy]

I would looooooooooove if someone could create a mod or if there is a mod for when people sign up, they can choose secondary usergroups that they wish to be in upon registration.

Something like check boxes for each usergroup.
I am running vbulletin 3.6
I am happy to give a years worth of top banner advertising on my website (in my sig).

Thanks vb!