[StevieG]

Here's another interesting bit

% of non-deleted users with custom titles: 1.1%

% of posts from non-deleted users with custom titles: 24.8%

% of non-deleted uses listed as Carpal \'Tunnel: 0.7%

% of users that are listed Carpal \'Tunnel: 25.4%

Adding that up, under 2% of users are responsible for half the posts.

As far as the 80/20 rule goes, you need only take the highest 5% of posters (those with around 530 or more) to get to 80% of posts.