Python PowerSet.py

def PowerSet(base):
    power_set = []
    b = len(base)
    map(lambda g: power_set.append(map(lambda x: base[x],
        filter(lambda x: g[x], range(0, b)))),
        map(lambda value: map(lambda x: (value >> x) & 1, range(b - 1, -1, -1)),
        map(lambda value: value ^ (value / 2), range(0, 2**b))))
    return power_set

print PowerSet([1,2,3])