Would this be a setting or a hack?

[Gronilot]

I want to show which post number in addition to users total posts.

For example... If this was the 12th post I ever made........... and I go on to make 419 (this number would increase as I posted more) below my user name, later when people went back to look at this thread it would say "Posts: 419" I want it to say "Post 12 of 419"

The type of board I want- it would be relevant of how early someone made the posts- it would be a pain to go compare dates and times.

Thanks.