Cross-dominance.

They always say one thing leads to another. I was sitting here, listening to Bach's Brandenburg concerto 5, reading my music book when I decided to search for tremolo (because Vivaldi invented it). 

Tremolo on guitar is hard for me now because I cut my nails. Stupid short fingernails. 

Anyway, I searched tremolo and somehow ended up reading up on "hand dominance". Which translates into right-handedness, left-handedness, cross-dominance and ambidexterity. 

If you've got right-dominance, you usually use your right eye, ear, hand and leg the most, because the left side of your brain will pick up signals more dominantly (or something like that. Quote: I am not an accurate source). And vice versa for left-handers. 

"To determine Handedness: Assume for handedness that your handedness is the hand with which you would normally pick up a pencil and write. For ambidextrous people, use whichever hand you would first impulsively pick up a pen with... if that doesn't work, use the leg-crossing test. If when you cross your legs, your right leg goes over your left, then you are probably right handed.

To determine visual dominance: Several step process...

1) Choose an object a couple feet away.

2) Place your hand with the "thumbs up" sign, so that your thumb is covering or at least partially covering the object you chose. Your thumb should appear somewhat translucent, and should be covering the object.

3) Choose an eye. Close it.

Your thumb will do one of two things: 1) It will turn "solid" looking, and will remain covering the object. 2) It will turn "solid" looking, but will appear to move slightly to the right or left of the object.

If you close your eye and the thumb appears to stay in place, then the eye that is open is your dominant eye. If you close your eye and the thumb appears to move, then the eye that is closed is your dominant eye.

4) Repeat, closing the other eye.

Your thumb will do one of the two things above. The results will be the same. If neither eye appears dominant, then you may have uncorrected visual problems.

To determine ear dominance: Whichever ear you put the phone up to is most likely your dominant ear. That failing, whichever way you turn your head when listening to someone carefully. This is the least reliable one to test for...

To determine foot dominance: Whichever foot you normally put the most weight on when standing in a relaxed state. If you have been brought up in a military type setting, and stand with your weight equally balanced, then whichever foot you would normally kick a football (soccer ball for us Americans) with."

- http://www.addforums.com/forums/archive/index.php/t-11609.html

I tested myself, and found out I'm right-handed (I write with my right hand, though I can write with my left and cross my left leg over my right), right-legged (though I prefer to balance on my left when I do Taekwondo), can't have a dominant eye because I've got shortsightedness in one and longsightedness in the other and both have astigmatism, left-eared, and can't tell the difference between right and left of most things and myself. 

I fail.