Guest post but also give a name that will be displayed in postbit

[Blackbeard]

I was woundering if there is a hack or if someone can make a hack/plugin that will allow non registered guests to be able to add a name registered members could call them by.

I want to all guests to be able to post help questions on my forum without having to register, then maybe they will see the benifits of registering on the forum and join properly, want i dont want is aload of guests as names

so if they add say Jon, in members nick area it will say Guest Called Jon in the postbit