IP Ghost
Allows admins to make certain users' IP disappear from the logs.
Ghosting adds two extra queries to every page because the plugin has to erase the IP address from all ghosts' sessions.
Install
Upload the contents of the "Upload" folder to the root of your forum.
From ACP -> Plugins -> Install and Activate "IP Ghost".
Upgrade
From 1.0 to 1.1:
Upload contents of the Upload folder to the root of your MyBB installation.
Support
This plugin is NOT maintained and NO support is officially given by the author. Use at your own RISK.