: Requiring
: pre-registration with email verification is one technique, but it means
: another password to try to remember.

This seems like a simple solution with virtually no downside. I find it hard to believe that people couldn't deal with another password, especially considering that browsers can be set to remember user names and passwords and enter them automatically. If you explain that registration is required in order to post primarily as a hedge against spam, I don't think you'll see much resistance.

: One reason I stick with the existing BBS script is I like the dialog flow it
: promotes. I have not found a modern BBS that does it as well or better.

I agree, it's still the best out there.

: The price we pay is having to see some spam.

It doesn't have to be that way, as you stated above. Please, just institute registration and be done with it.