Marcus (aka @msykes)

This plugin removes the admin bar completely from the public and admin areas of the website. Can be used either as a normal or MU plugin.
Upon activation/installation this works immediately. Nothing fancy, the admin bar is just not loaded anymore.
<h4>BuddyPress 1.1 Onwards</h4>
You can also add the following to your wp-config.php file and then you don’t need this plugin ( sniff ;( ) :
<pre><code>define( 'BP_DISABLE_ADMIN_BAR', false );
</code></pre>

Remove BuddyPress AdminBar

This plugin removes the admin bar completely from the public and admin areas of the…

Michael Dance

This humble plugin adds an option in Settings > General that controls who sees the WP Toolbar when viewing your site.
You can turn the Toolbar on or off per user role.
Note that this controls the public, front-end version of your site. When viewing the dashboard, the toolbar always appears.
How is this different from other plugins that do similar things? It’s smaller, cleaner, and doesn’t add any unnecesary settings pages. It’s also smart enough to hide the Toolbar option on user profiles if that user is already restricted from seeing the toolbar.

Disable Toolbar

Control who sees the WP Toolbar when viewing your site.

Remove BuddyPress AdminBar vs Disable Toolbar