Abuse of admin privileges 

I have caught you vandalizing my user page and user talk page.  I don't know who you think you are or who you think I am, but if you don't go back to my user page and undo your vandalism and mark it as vandalism, this is about to get REALLY, REALLY fun for me.  )

I know admin privileges are not easy to get and you've probably wasted a large portion of what could have been a useful life achieving that, so I'm thinking this might, just might, be important to you.