Mitosterbation 

Sex with a clone of oneself.

"We did not clone you for mitosterbation. At least get out of my office!"

Mitosterbation by Qman3000 August 17, 2008

Mathsterbation 

Working really hard on a sum just for the feeling you get once you have solved it.

Guy #1 "OMG what's Elliott doing with his math book?"
Guy #2 "Eww! he's Mathsterbating!"
Guy #1 "So that's why he's sweating so much! Have fun with your Mathsterbation, Freak!"

Mathsterbation by Disco Alpingu April 1, 2007

Mathsterbation 

Mathsterbation is the act of masturbating when a maths problem or assignment becomes too difficult and/or tedious to complete. It is often practised when the subject has lost all hope in completing his maths and can see no other option.

Friend 1: Hey, what did you get for question 4?

Friend 2: *fap* *fap* *fap* Go Away!

Friend 1: Mathsterbation already? That's weak...

Mathsterbation by highoffmathsfaps November 5, 2013

Mindsterbation 

When your mind is only focused on having sex with a hot celebrity and your girlfriend, to where absolutely nothing can break you from your sexual daydream.

Billy: Dude what's wrong with Hunter?

John: He's thinking about having a 3-way with Katy Perry and his girl Emily.

Billy: Classic case of Mindsterbation?

John: Yup.

Mindsterbation by A pro mindsterbator August 11, 2010

misterbation 

Similar to masturbation, but without completion. See also doctorbation.

Suppose you have the last name Bate. Surely by know you have heard many jokes about being called "Master". But even a proper title can be funny.

I barely had time to misterbate before the bathroom door was rudely opened.

misterbation by Rage from rhuvok.com July 27, 2003

Mindsterbation 

derived from the term mind-fucking, where when mind fucking one self, one tends to mindsterbate, therefore the word directs towards the situation to when a person is fucking with ones on mind he tends to be mind-fucking

Joe: I have been fucking with my mind, with all this arithmetic and alcohol

Harry: Yeah dude I guess mindsterbation of a higher form

Mindsterbation by Maverickan September 5, 2012