I posted this as a comment on Palochi's site; I thought it was amusing.

a + b - c = d

a = rugger
b = beer
c = women; a civilizing effect, especially for the straight boys who are trying to get into their pants
d = wild times

xa + xyb - c + e = d to the power of xy

x = a number greater than one, likely around 30 (the minimum number of players on two rugby sides)

xy = the number of ruggers (x) times the number of beers each will consume (typically between 6-10)

e = rugby songs, joyful hymns to drunkeness, deviant sex and rugby; a strong uncivilizing effect

d to the power of xy = puke-in-the-street-wake-up-with-a-stranger wild times