The act of several guys (most commonly only two, due to logistical issues) standing around a toilet and urinating at the same time, often to save time, but also done as a drunken male bonding exercise. When the beams are crossed the Star Wars inspired phrase "I am your father" is often said due to the analogy to a light-sabre fight.

Be careful of spray. Also shouldn't be attempted with too many people at once and you should know/trust the other people, or they might piss all over you.

Also, do not try to recreate the scene where Anakin's arm is cut off.
1) Person1: I gotta go piss.
Person2: Same, but we gotta hurry.....Let's do crossbeams.

2) I am your father!!!

3) It's not the size of the light sabre that counts, but how you fight with it.
by your_father January 12, 2006
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