Emails Per Day. The amount of email sent/received from a single contact in one day.
I average 13 EPD with my BEF (best email friend)
Explosive Projectile Diarrhea. When your ass is not only shooting out liquid shit, it's also shooting it great distances.
Alex - "I just had Taco Bell for the first time in five years for lunch."
Me - "Looks like you're going to have some EPD tonight."
Alex - "Worth it."