Remove the Ink Preference Pane
Couldn't find this anywhere on the internet so I though I make a post of it.

When you use a Pen Tablet or similar input device OS X adds a Preference Pane called Ink to your System Preferences.
When you are using a Tablet it can be handy to have it, but if you sell or give away the Tablet you may notice that it lingers behind and you can't right click it to remove it.

Deleting the Preference Pane would get rid of it, but since Ink belongs to the Core System it is not recommended that users go that way.
Instead deleting the plists that tell the OS that Ink should be displayed is the preferred way.
This way everything is just like before you used the Tablet, and it will not come back after a system update.

Delete the following files located in ~/Library/Preferences/ and the Ink Preference Pane should be gone after a restart.