mitcho (Michael Yoshitaka Erlewine)

Require first and last name from users who are editing their profiles.
The HTML5 <code>required</code> attribute is added, the text “(required)” is added next to the fields, and the data is verified to be non-empty on save.
Development of this plugin was supported by the <a href="http://globalshakespeares.org/" rel="nofollow ugc">Massachusetts Institute of Technology Shakespeare Project</a>.

Require First and Last Name

Require first and last name from users who are editing their profiles.

Skyy

This plugin allows you to banned certain username from making comment, particularly when you don’t want to ban 
ip addresses, but want to stop certain “notorious” misbehaving users.
If your blog requires user registration, you should really try the “members.0.1.1” wordpress plugin.

Require First and Last Name vs WP-Ban-User