unbrewlib.py

import os
from os.path import *
import shutil

brewdirs = set()
for r, d, files in os.walk('/usr/local/lib'):
    for n in files:
        f = join(r,n)
        if islink(f) and "/Cellar/" in realpath(f):
            dirs = f.split('/')
            brewdirs.add("/".join(dirs[:5]))

for path in brewdirs:
    shutil.rmtree(path)